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Chevy Colorado and GMC Canyon Electrical Problems



  • I see that you have already been in to the dealership, and we're available to follow up with them, if you like. We would do so by setting up a Service Request; if you are interested, please send us an email with more information, including your name/Edmunds username, phone and address, the last 8 of your VIN and current mileage, and the name of your involved dealership.
    GM Customer Service
  • den052den052 Posts: 27
    Northerngirl11: Sounds like a switch inside a door is open. Each door has a switch (not sure where it's located), that signals the BCM when a door opens or closes. That is how the BCM knows to turn on the dome light and cut off the radio or etc. It works much like the old dome light plunger switches worked when you opened an older car door. It is either a plunger that actuates when the door is open or closes, or it is probably mounted and actuated by the door latch mechanism. Better take it to a more professional GM dealership as they can read the status of the switches and tell what door is giving the problem. If the dashboard indicates a "door open" condition while driving even though all the doors are closed, this is the problem. I have software on a laptop that I can diagnose GM body computer functions and etc. I am located in Michigan and probably too far away to help you with that.
    Did my son's Ford truck he bought used. Someone disconnected all the dome light and fuses and etc because a door switch was open and the BCM "door open". Used the software to determine that the right rear (quad cab) door switch was open. Pulled the right rear door panel and located the bad switch and replaced it. It saved pulling all the door panels to find the problem.
    Dennis Tomlinson, Master Mechanic
  • I got my truck back from the dealer a week from the day it broke down.They had to order the fuse block from the U.S.. Took 3 days just for the part to arrive.After speaking with the dealer before they fixed it,(they told me there were no bulletins or anything else that would cover the cost),i called GM Canada and complained. Told her that i shouldnt have to pay for a new fuse block on a 4 yr old truck. As well as the vent valve on the gas tank. She said she would call the dealer and talk to them. Anyway,Gm wouldnt cover anything. The dealer called and told me my truck was ready. I said i would be in later to pick it up. The bill was $1498.44 for the fuse block and vent valve. She told me on the phone that she would pull the truck inside sometime that day and thaw it out as there was snow on it. I said " Do me a favor. When you pull the truck in, check the drivers side window and locks". I explained how people have gone in to pick their truck up and went to leave and the window lock issue blah blah blah didnt work. I got off early and went to get the truck.She hadnt pulled it inside yet. I went to pay this awesome bill,while she was bringing it inside. When i came back, she was just getting out of the truck.She said" The window doesnt work"!!!! LOL. I chuckled.She said the technician would need to reprogram the bcm. He takes it for a drive and comes back. About 10 minutes later she tells me that the techs cant figure it out. She said that there was 4 of them standing around scratching their heads!!!!! LOL. She says "we dont know what the problem is.It could be the window motor or...." I said "Whatever. I dont have anymore money to spend." I told her about this website and that i would figure it out myself. And she let me go!!!! Walk out the door without my window or locks working.Got home and disconnected the battery for about 8 hrs and reconnected the same way i did last time and it didnt work.Then GM canada called! She asked me if i got my truck back and how was it.I explained the story and told her all about this website,and the ever ongoing problems with this issue. She said i should take it back to the dealer and tell them that it worked when it was brought in. I said" Well the fuse block was replaced so they will just say no it didnt work when it came in. She didnt offer to fix it for free when i was there so I'm not going back to fight with them. I'm tired of always having to fight with people." She said that without taking it back she couldnt help me. I said " O well, I'm not taking it back." So she made a note in the computer about the window/lock/remote issue and that was it. I disconnected the battery again and reconnected. Still doesnt work. So I guess I'll take the door apart and check the module. I havent put the truck up for sale yet,but am seriously thinking about it....... Good times... :lemon:
  • Hey Shyster,
    Check out my posts #426 and #438 in this discussion. This fixed it for me. I had partial luck pulling the battery cable but I think the only reason that worked is that you had the hood open and changed the temperature on the loosely fitting clips on the fuse, causing enough expansion to make an electrical connection. The extra strands of copper I shoved in with the fuse helped insure a strong connection, and while not elegant, hasn't failed since.

    What bothers me is that they just replaced your fuse box and you still have the problem. Check the power lead in your driver's door switch with a voltmeter to see is the hot 12V input to the switch drops to almost zero when you hit the switch to move the driver's window. That will tell you the line from the fuse box can't push enough current through to do the job. The weak link is usually the clips griping on the fuse.

    Good luck!
  • "About 10 minutes later she tells me that the techs cant figure it out. She said that there was 4 of them standing around scratching their heads!!!!! LOL. She says "we dont know what the problem is.It could be the window motor or...."

    Another fine job by GM service techs.

    Remember the first rule of Feregi acquisition, "Once you have their money, you never give it back." GM has the same attitude.

    A $1400 bill!!!! OMG.

    I'm surprised the "I appologize for your frustration" people haven't tried to scavenge this thread for a while. I guess 'Peggy' is finding greener pastures someplace else.

    GM= :lemon:
  • Yeah hey where's all the CONCERN from Christina and the rest of the G.M. Cust.Serv.Staff?? NOOOooo" dealerships to reccomend" in this persons area? Snaproll1 is right seems "PEGGY" is finding greener pastures..

    Do yourself a BIG favor shyster66 GET RID OF THE P.O.S.!!!!!

    G.M. dose'nt care neither do thier dealers/serv. depts.!!

    Randy Wise Chevrolet Milan Mi. THE WORST DEALER ON THE PLANET!!!
  • snaproll1snaproll1 Posts: 88
    edited February 2012
    Hey, one other thought to try with the whole window/fob thing. Disconnect the battery leads, wait a bit, then touch them together for a while. Someone a while back mentioned that possibly capasitors may be holding a charge that is keeping computer codes from clearing. I know it sounds weird, more like voodoo but with a the electrical problems of the Colorado, I don't think it could do any harm. Somebody said this worked for them.

    My guess is replacing the fuse block fried something, most probably the door modue. Hit or miss, you can try replacing the door module and it may solve the issue (until it fries again).

    For what it's worth that fuse lock was covered under warranty for me but they said it was like $400 dollars.

    Your best bet though, sell the truck and be money ahead in the long run.
  • shyster66shyster66 Posts: 17
    edited February 2012
    Isnt it ironic though, that I told her to check the window and locks b4 i got there? The only reason I knew that was because of this site. And why is it that every dealer has never heard of this problem? My dealer in Woodstock, Anderson's never heard of it. The lady from GM Canada never heard of it.We should see how many dealers that we know of have never heard of this.Start a list or something.Ok, I'll start.

    1. Andersons Gm in Woodstock Ontario Canada
    2. GM Canada
    3.Randy Wise Chevrolet Milan Mi.

    Ok Snaproll. Go through all the posts and fill this list in.LOL. It would be interesting to see how many we could come up with.j/k
  • Good morning,
    Still hanging around. As shyster66 is located in Canada, I was unable to offer to assist further. I realize that there may not always be interest from some community members in what I can assist with, and didn't want to spam the wall.
    All the best,
    GM Customer Service
  • Decided to fix one of my many electrical problems this morning. Went by the dealership to order a blower motor resistor and wiring harness. Could not believe that when he gave me the total, it was $15 more than Thought I could save a few $$$ on shipping by ordering local. What a scam!!! As soon as I get the blower motor working, I am selling my GMC Canyon. I will never purchase a GM vehicle again.
  • I'm sorry that your Canyon wasn't a satisfactory vehicle for you, and I really do hope that your next vehicle is more successful!
    All the best,
    GM Customer Service
  • Sounds like yet ANOTHER happy satisfied customer to me. If Chevy can't/won't take care of all these electrical issues HOW in the heck do they think thier trucks can get through "armagedden." like the Super Bowl commercial says??

    Randy Wise Chevrolet Milan Mi. THE WORST DEALER ON THE PLANET!!!
  • "I'm sorry that your Canyon wasn't a satisfactory vehicle for you, and I really do hope that your next vehicle is more successful!"

    Well, my Colorado was a "satisfactory vehicle" when it wasn't having weird and expensive electrical problems because of the design flaws. My next vehicle has been "more successful" because it is not a GM product.

    Honest, Sarah, Christine, Cameron, Peggy or whatever you go by, honestly, what can you actually do for the poor folks that still own their Colorados and Canyons and haven't traded them or junked them yet?
  • I own a 2005 Chevy Colorado Crew Cab 4X4. The motor is bullet proof, but the electrical system is a mess. Once in awhile it won't start for no reason. It turns over and over but no fuel to fire it up. This turns out to be the ignition cyclinder ($37 part) and passcode sensor ($85 part) that is faulty. Cheap fix right? Wrong. Nearly $200 for labor to install and "program" them. So I'm looking at over $300 so my truck will start. All this while GM knows this is an issue in EVERY Colorado eventually. My Toyota has 342,000 miles on it an still has the original ignition and theft system. Now my driver window and locks won't work. Occasionally the front passenger window works, and then it won't... it's kind of like winning the lotto if it works. GM tells me it's the switch module that's bad. $238 just for the part. They even said $60 to install the part, LOL it's two screws, my 10 year old daughter can change it in 3 minutes. I'm getting these issues fixed and selling or trading it before the weekend. I have my new Ford F150 picked out at the Ford dealer right next to the Chevy dealership. Sticker is $49,345 and I promis you Chevy will never see a penny of my money again. And I work for GM and get the employee discount, almost $3700 off a new Silverado. No thanks, my days of bad bow ties are over.
  • den052den052 Posts: 27
    edited February 2012
    Unfortunately most vehicle manufacturers are going to body computers with the associated problems. Commonly, maybe all you need to do is to pop out the drivers door module and lube all the plugs with di-electric grease (also the pax door too). Sounds like your other trouble was with the anti-theft system which turns off the fuel if it cannot recognize the key.

    A friend of mine had a GMC Envoy that the drivers lock/window module burned up internally. Replaced the module with a brand new one but here is the clincher!!! The window/lock module has to be PROGRAMMED to the vehicle for it to work!!! What a bunch of crap. I called around and got estimates from $50 to $100 to program it (a 15 minute job). $50 is not too bad so he will have it done there.

    The problem is that Car manufacturers charge about $1800 a year to access their database for programming files. The equipment to do it also costs a boatload. The Lawmakers need to do something actually useful and put laws through that if a company makes vehicles with computer programs and updates, that it needs to be FREE or very low cost for all repair shops to be able to work on the vehicles.

    With computers controlling most of the body functions now, it is actually easier and cheaper to WIRE the vehicles. For instance all functions of a drivers module (ie door locks and windows and etc), can be sent to the body computer using a single wire. Before this, a drivers window switch had all the wires from the other doors passing through it before going to the other door buttons and etc.

    The problem is that if it is cheaper to do this, you don't need to charge to update or program different modules to work when they go bad.

    Forward this letter to CONGRESS LOL LOL LOL

    Dennis Tomlinson, Licensed master mechanic
  • snaproll1snaproll1 Posts: 88
    edited February 2012
    "Forward this letter to CONGRESS LOL LOL LOL"

    Congress? You mean Obama.

    He needs that BCM repair money rolling in so that it can become campaign contributions.

    GM= :lemon:
  • princelee420princelee420 Posts: 1
    edited February 2012
    I totally agree. No more Chevy's for me either! I grew up living and loving chevy's and my dad will probably disown me for pulling up in a ford, but I've owned two F150's in the middle of all the different GM products I've owned and never had the trouble with them that I do with GM or my 2005 Colorado. I've probably spent over 2000.00 on my truck in the past two years just keeping it on the road. I just put in my 5th window regulator. My driver window and door locks have been on the fritz for the past couple weeks now and its 35 degrees outside and my window is half-way down! My service engine light comes on constantly. My ABS light comes on at least once a day! I've had a bearing on the front driver side go out while driving down the interstate; total bill 735.00. My radio died and would not spit out a cd so I had to replace it as well. Now my windshield wipers will not turn off. I've changed the motor and relays. Now waiting on my wiper switch to come in the mail so I can replace it to see if that is the problem. Last but not least I can not turn on my headlights at all. I can wait till it gets dark and let them come on by themselves, but if I turn the switch to the on position they go off! Not sure what to do about that one yet! I would hate to see the bill If I had taken this to a dealership for every instance. It would probably be well over 4,000.00 to pay their hourly charges. If the Lord's willing this will be the last Chevy :lemon: that I will ever own!

    FOR SALE: 2005 Chevy Colorado 130k miles. 4x4 Crew Cab :cry: :(
  • Ah and yet another happy customer/fan of the Colorado! are ya listening "PEGGY?"

    Randy Wise Chevriolet Milan Mi. THE WORST DEALER ON THE PLANET!!
  • I had to change the battery for the first time on my 2005 Colorado yesterday. Now my door locks won't work, drivers window won't work, and I did notice the heater for a split second would go off then back on. So by reading all of these posts, this is just how it is for this truck? Geez........Only has 88,000 miles on it and only about 1,500 of that was mine as I bought it in 2009. How sad that they know this is a problem!
  • den0520218den0520218 Posts: 2
    edited February 2012
    luciro: If you pop the drivers door module out using a table knife or wide screwdriver, just unplug the module. Apply dielectric grease available at a parts store to the connections. Replug the connections and try the switches. Mine has been working ever since (knock on wood). The fact that you switched batteries really has nothing to do with the door lock/window problem. It was just that it happened at the same time. Believe me, as a mechanic for over 40 years, I have disconnected and reconnected my share of batteries and the minute you disconnect the battery you shut down both the engine and the body computers totally. When you reconnect the battery cables, the computers come back on and initalize like they should. As a matter of fact, the vehicle computers are HARD WIRED and the computer program is burned into a chip. The only way you can change the programming on them is to REFLASH the memory chip with a special tool called a TECH2 for GM. They operate totally different than your home computer and as of yet is not possible to have a VIRUS. It may be possible to introduce a virus, but as soon as the power is removed the virus would be lost and the computer would reinitalize from the onboard read only memory that cannot be changed without a reprogramming tool. So in other words, it would be impossible for a virus to replicate itself from one vehicle to another because there is no removable memory as of yet such as a hard drive.
    Of course this is the current technology and that could change as it has been discussed that virus could pose a problem in the future with different forms of memory devices. As of today, current vehicles cannot harbor a virus.
    I am a master vehicle technician but also a computer technician too.
    Dennis Tomlinson
  • Thank you so much for your prompt reply. I sure hope I can get this corrected. Very disheartening reading all of these posts on the same problem. Really makes me think I should get rid of it before anything else goes wrong. Again, thank you so much for your help!
  • This happened to me when I cleaned the battery terminals one day. I had left the drivers window down when I did this. After reading and trying many of these posts on how to fix it, none of them worked. I finally took the drivers door window switch appart and jumped it directly to the battery and rolled the window back up. I went to back the truck out of the shop and the locks worked and the windows worked. When I finally had to change the battery, I made sure the drivers window was up, no problem this time. I have 152,000 miles on this 2005 Colorado Crew Cab. Just took it to Florida from Colorado and didn't have any trouble.
  • I read further down that you couldn't help someone because they were in Canada. . . well I guess that means you can't help me either!
  • "As a matter of fact, the vehicle computers are HARD WIRED and the computer program is burned into a chip. The only way you can change the programming on them is to REFLASH the memory chip..."

    Hi Dennis,

    I don't believe this is entirely true. I'm not intimately familiar with automobile computers but I do know a bit about them in general. Granted much of the executable code on these BCMs, ECMs etc must be read only, there has to be some writeable areas (at least e-proms or flash memory) to store error codes etc.

    I'm wondering if with the truck's electrical glitches some bad program code gets generated? Here's an example. Let's say the BCM is "programmed" for a particular body style (two or four door) and installed options (side airbags, Onstar etc). This stuff would have to be factory programmed and remain unchanged during the life of the vehicle. What happens if because of the crappy grounds on the truck, the shorting fuse blocks and other electrical gremlins, these prom areas get smoked? Either they get changed to non-comprehensible codes or literally do fry from a voltage surge?

    Here's a 'thought' of where I'm going with this. I have no ideal how close I am to how these computer systems work, but I have to be in the ballpark. Let's say there is a programmable longword, (32 bits) in the BCM. Each bit represents whether some elecrical subsystem gets power depending on the vehicles options. If a bit is set, the option (horn, airbags, windows, door locks etc) get power. The eprom gets programmed at the factory. Life is good, up to the point of a voltage surge, faulty ground or disconnecting connector socket, buring up blower resistor etc. This causes a voltage spike which fries or reprograms the eproms on the BCM. In short, bits get flipped or cleared. Now you have power being sent to wrong circuits at the wrong time (possibly tripping other error codes) or causing really weird and unexpected results, (the kind of weird stuff people have been reporting on this truck like turning the radio on causes the windshield wipers to work).

    It also explains why sometimes disconnecting the battery can work. If the eproms remain ok, and just weird error codes were generated, disconnecting the power would allow these codes to reset and things would be ok until the next glitch.

    Of course you don't suspect this so you take the vehicle to a dealer. They read the scrambled codes and deduce that "the BCM is bad" and happily charge you for replacing a perfectly good BCM. When the problem happens the next week, they say the BCM is bad again, and again, and... the Colorado/Canyon becomes the gift that keeps on giving... to the GM service departments.

    In the meantime there are the real electrical and mechanical problems that crop up that could cause the whole thing. The bad grounds. The poor electrical connectors like on the blower resistor. The crappy CD player that can't read half the CDs you put in it. In other words, just poor GM design and lack of quality. These things fry and potentially start the ball rolling and the whole electrical system becomes unstable and unpredictable.

    Otherwise how can you explain some of the weird things people have reported? Just weird stuff like, "I turn on the radio and the lights go off" or what was that last deal a few posts ago, "I turned the ignition and the truck wouldn't start. When I turned the key off it started cranking". How else can you explain weird stuff like that other than a computer controlling everything getting scrambled? How else can you explain just letting it sit with the battery disconnected for 6 hours "fixing" anyhing? Obviously something elecrical had to "clear" for this to sometimes work. Why doesn't to work all the time? Because all these problems probably do cause things lik the BCM to eventually fry.

    I've been following these reoccuring problems with the Colorado/Canyon since 2007 and after this much time, that's my "theory". The pattern makes sense, at least from a computer standpoint, but again, I have no cluse if I'm all wet with how they work in vehicles.

    If what I'm saying is somewhat true, there basically is no way to "fix" the vehicles short of ripping out all the electronics, electrical system and computers and redesigning them. Every ground would have to be checked, scraped and ensured of a good contact with the body. All underperforming parts like the electrical connectors on the blower resistor and frying fuse blocks would have to be replaced. The alternator would have to be beefed up. The list goes on.

    Now I think you have an idea why GM will never acknowledge the problems with the truck. There were too few of them sold to justify such a huge expense just to satisfy so few customers. Much better to write off the truck and their owners, (especially when the only customer that really matters is their CEO Obama).

    So GM writes off the truck and the owners, with one exception. Why pass up on all the lucrative repair money? So they invest to have "Peggy" prowl the forums, "appologize for your frustrations" and try to drag the truck owners to the nearest dealership so they can get their commissions.

    The bottom line on the Colorados and Canyons is pretty clear. Get the truck working the best you can and dump it. If my scenario above is correct, the truck will never be "fixed". It will continue to be a money pit. You don't need an extra weird electrical problem every six months that costs $500-$1000 on average to fix on top of the normal expenses on an aging truck. Trust me, I know. I really loved my Colorado.... up until the fourth or fifth weird and expensive electrical problem.

    There are enough vehicles out there like the Toyota Tacoma that do the same job. Toyota and the others stay in business because satisfied customers still mean something to them, where GM depends on government bailouts and the Chevy Volt as their future. (So what if they don't work as advertised, Obama is the only one they need to impress).

    I finally gave up on my Colorado but still follow this thread. Hard to believe it is over 600 posts. And still, every week there is somebody new that finds this thread with the same story, window/fob (or some other weird electrical problem) and with the same, "the dealer said they never heard of it" reply.

    What else can be said? GM= :lemon:
  • den052den052 Posts: 27
    Yes, snaproll1, you are somewhat correct in that there is an area in vehicle computers that is called "volatile ram". This area stores the engine or body code used to help troubleshoot problems. This area is also used to store data used in "learning curves" for engines especially. For instance, the engine computer stores data it uses to know how much "fuel trim" is needed for a particular vehicle. It learns this by recording how much extra (or less), fuel is needed beyond the programming amount to make the exhaust exactly 14.7 to 1 oxygen to fuel mixture. Transmission computers use this area also to learn smooth shift patterns in much the same way.

    Before 1996 (OBDII), when someone disconnected the battery. The codes and the small amount of learning data were lost. A few drives and restarts re-established the learning curves. Now with OBDII and beyond, the technician has to use a reader to clear and remove learning curves (fuel trim, shift data, etc), from the ECM or Body computer. Usually by clearing the codes by a reader it also flushes the learned data also. We always caution the customer that your vehicle may perform slightly different for a couple hours or less after clearing codes. Most are unable to notice a difference though.

    Every time you turn off your vehicle (as of yet), the computers shut down except for this small kept alive memory. When you turn the key back on, the computers have to initalize and start reading the burned in instructions to execute from ROM. Therefore, (as of now), it would be virtually impossible to execute wrong code including a virus or for the existing computer instructions to get corrupted. Remember, the instructions are contained in ROM or "Read Only Memory". Yes the computers look at the RAM area for data that is contained there but no computer instructions are in this area.

    With PC's and Laptops, this is a totally different story. When you turn your computer on, the first thing the processor does is to read BIOS for the instructions to access the hard drive. Once it starts reading the hard drive, it is picking up computer instructions on how to execute Win98, WinXP, Win7, or a host of other operating systems that you as a user can install on the hard drive. This is where a VIRUS loves to be. Malicious code can be written to a hard drive that replicates itself on CDROMS, FLOPPY drives, Memory sticks, Internet programs, and etc. This code can be carried to other computers and cause the new computer to write these instructions on it's hard drive and continually replicate itself to other computers.

    Yes, a trained technician can FLASH a new ROM onto a vehicle engine computer or body computer. However, this is only allowed if there is an UPDATE available from the manufacturer and it takes special tools and usually a $1800 a year fee to do these operations. So dealerships are usually the only ones that are able to do this. There are also safeguards when programming that checks the "Checksum" at the end of programming to see if the code installed matches exactly; otherwise a message pops up that says "Programming Unsucessful".

    When I had my window/lock problem, all the other functions on the body computer for my Colorado worked perfectly. The radio would turn off when the doors were opened. The dome light would go off at night when the key was inserted, and all the seatbelts, low fuel, alarms, and etc worked flawlessly. The only thing that didn't was the drivers door window, and the locks. The parking lights would flash with the fob but no lock activation occured. This told me that the body computer was acting normally and was intact. Yes Murphy's law is still possible. The body computer could get corrupted. But simply a turn off of the vehicle and a restart would re-initalize the computer sequences and would be ok again. If you noticed, quite a few people tried disconnecting the batteries and etc and it didn't fix the problem. Some said it did and others said it did not help.

    With all this said, I am only human and maybe someone can show me that I am all wrong. If so, I am happy with that also.

    Catch you later, Dennis
  • Thanks for the reply Dennis. I'm still thinking there has to be some kind of "programming flaw", the old "garbage in garbage out" scenario.

    Again, I have no idea how 'code' is derived in vehicles but I do know a bit about computers and coding itself. You're making the assumption that the ROM code is "flawless". I have seen really weird things happen with low level code, "programming errors" that are so subtle they are nearly impossible to find. They are nearly impossible to reproduce because the confluence of circustances that cause them are so obscure. It might be an obscure piece of code that runs but whoever coded used a case statement that doesn't address that particular condition, or there is a missing return or something, no error handling and the code thread falls through executing some other instructions out of sequence that screws up something else, which in turn screws something else up until the BCM is hozed. Maybe when the ROM was being written somebody coded an incorrect label and the code thread shifts to some nonreadable data area and the BCM is hozed.

    Right from the get-go these trucks had weird electrical issues. Here's an example, I've heard similar storied from a couple of other owners... When I got the truck I wanted to make sure the door key worked. I tried it in the lock and the horn started to 'toot' lightly as the door unlocked. A few seconds later it started the "somebody is stealing me!" scream. I hit the panic button and it stopped. Kind of shaking my head I looked at the GM sales reps, and asked what the truck was doing. Sheepishly they just kind of shrugged like, "Ummmm, that's the new... ahhh, horn-test system I guess?" They had no clue, we kind of figured it was some kind of "new thing" that would be explained in the manual. Of course there was nothing, so maybe it was something "undocumented"? Perhaps, but my guess is it was the first sign of some weird programming error.

    The more I think about it, the more I have to think the majority of these problems have to be computer and/or code ("programming code") related. The reason I think this is because some of the weird electrical stuff would be hard to explain if it was simply 'physical' problems like frayed or shorted wires. Things like that don't usually "get better" or heal themselves, but computers can and do. With a computer a weird set of circumstances and poorly written code can can screw them up and likewise a weird set of circumstances (disconnecting battery leads, putting the key in the ignition at the right time, turning on the lights, some kind of sequence of inputs) can heal (reinitialize/clear) them.

    How else can some of the weird stuff be explained like turning on the radio locks the doors or whatever. I guess it could be physical like shorted wiring, but it sure as heck sounds like poorly written process control code.

    Again, I'll be the first to say I may be completely off base and this stuff and what I say is impossible, but for a moment let's say it is possible... Say some highschool dropout at GM was writing the BCM control code and was still stoned from lunch and kind of forgot a return instruction before sending the code off to be burned as ROM into 16 million BCMs. Everything looks ok and the problem doesn't get discovered until that particular piece of code gets executed, something like, the lights have to be off, the radio on and the air conditioning on when the truck is turned off and the key left in the ignition with the dome light left on for over 20 minutes. Maybe that piece of code gets executed when the BCM realizes the dome light is still on and the code is supposed to turn it off. It does, but rather than return to wherever it is supposed to go, the thread falls through into "the twilight zone". Somewhere along the way it turns power into the drivers window relay and shorts out the little chip in the drivers window/fob circuit. This causes the battery to drain and with the low voltage fries something else when the key is put back in the ignition and the BCM fully powers up. Like I say, just some weird confluence of circumstances that happens every 6 weeks to 6 years. In the mean time, add in the poor grounds and wiring connectors and... you have a nightmare to solve.

    Let's say that scenario has even a grain of truth. What is the "proper fix"? Troubleshoot and locate the obscure problem in the code, do all the testing and debugging, then what? Produce new BCMs with the corrected ROM code? Recall all the existing BCMs in all the trucks? And if the code is written so crappy in one place, what's not to say there may be other code glitches that haven't been found and would be burned into the new BCM ROM anyway? For so relatively few customers? (The Colorados/Canyons were not big sellers). Factor in a company going bankrupt on top of this, would you elect to have a recall? Incurr all this expense? Forget it, just donate to Obama and get tax money to stay in business instead of relying on satisfied customers. We're back in business again, just sweep the Colorados under the rug except for the lucrative repair money... The guy that programmed the Colorado BCM was probably promoted to doing the electrical system on the Volt...

    Anyway, that's my rambling thoughts. I guess it really doesn't matter since GM is obviously not going to address the reoccuring problem that doesn't exist. It really would be interesting if there ever was a definitive answer but I doubt it will ever be determined for sure.
  • snaproll1snaproll1 Posts: 88
    edited February 2012
    Just a little FYI for all you Colorado/Canyon owners...

    Because of the Japan tsanami wiping out the competition, GM actually make a 7 billion profit.

    Of course the auto supply chain from Japan is back online now and next year projections for GM next year are grim. Their stock is still in the tank after you and I bought the company for Obama but does this concern them? No.

    While times are good and they have this windfall of money, do you think they might consider paying off their government loans? (Eh-eh, are you high?). Do they try to fix the electrical system on the Colorado? (You really are stoned if you might think so, why kills such a great repair cash cow).

    No.... they decide to give all their union employees a $7,000 bonus! (Way to go Peggy, spend my tax money well).

    GM= :lemon:
  • Well, this didn't fix my problem. But I guess it didn't hurt trying. Hate the thought of trying to take it somewhere, but I may have to. Thank you for your suggestions!
  • den052den052 Posts: 27
    Snaproll1: An interesting thing happened with a 2005 Ford E350 I was working on. I was servicing the batteries and connections because of a P0611 code: "FICM voltage problem or Fuel Injector Control Module voltage incorrect". This was on a 6.0l diesel. Tested the FICM and voltages were correct. There was a TSB out for re-flashing the FICM for random generation of the P0611 code without voltage problems. The customer was also complaining of batteries running down after a few days so I did a "parasitic battery draw" test. I removed the negative chassis ground and inserted a DVM measuring millivolts. I was testing how much draw on the batteries with everything turned off. As a general rule vehicle computers always draw a few milliamps of power for memory retention.

    I measured the draw at 65ma which is ok- anything under 100ma is good. However upon making and breaking the system ground, the power door locks turned on and activated a couple times during interruption of current flow.

    When I went to open the doors on the vehicle, they were locked and the keys were inside. Thankfully, the drivers window was wide open. That is one thing I generally do when working on a vehicle is roll the drivers window down. I just got in the habit of doing it over the years and good thing I did.

    The interesting thing is that the computer system called for the locks to activate when the computer system was unstable. Upon shutting off the vehicle and restarting it, things turned back to normal.

    So, end result is that you and I are both right. A glitch can screw up a body computer and re-initalizing the computer straightens it out (at least untill it screws up again). LOL LOL LOL
  • Hi Lucrio,
    If you have some time before surrendering it to the dealer, try this - take the driver's door switch out but leave it connected. On the blue connector there is an orange wire. This should have 12 volts direct from the fuse. Try to get a probe from a voltmeter into the back of the connector and put the other probe into the ignition switch (or another good ground) and see if you have a solid 12v. With the meter in the connector, try pressing on the lock and unlock to see if the voltage drops to 0.
    If it drops (and nothing happens) you most likely have a problem between that wire and the battery – probably the fuse connector in the fuse block. Probably the easiest way around this is to run a good 12v line with an inline fuse to splice into the orange wire.
    What I did was jam some copper strands in with the fuse legs, making the fuse legs a bit beefier and thus a better connection – it worked but I don’t know how long it will last – been working for a year so far.
    Good luck!
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