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Chevy Blazer GMC Jimmy Electrical Problems



  • cardoc50cardoc50 Posts: 49
    I have a 1997 Jimmy and ran into the same problem.I replaced the original pump and sending unit with a aftermarket one. Soon after my gauge would work until it got down to half a tank then would drop to empty. After a couple years the pump
    would not keep the pressure high enough to run right. It was only after I put in
    a factory fuel pump/gauge assembley that I got the right amount of pressure and the guage still works fine. I'm not saying that's whats wrong with yours but, that
    is what it took to fix mine. A GM mechanic friend of mine told me to put in the new GM pump
    and it would fix mine,and it did! You might think about checking your fuel pressure
    you should have 56 to 61lbs of pressure, I think I'd watch the mielage and guess on
    the amount of fuel left in the tank instead of buying another &300 pump. Again,
    it may not be the same problem I had but if it's not running exactly right and/or
    your fuel pressure is below specs it is worth looking into. Sorry I can't pinpoint an
    exact cause I hope this helps some.
  • I unplugged whatever was under the seat. I put in a new fuse and it might be OK for a day or two and then some times for only a few minutes but it keeps blowing the fuse. It has to either be the cruise control or the Body Control Module.
  • cardoc50cardoc50 Posts: 49
    Hello jlflemmons,I'm going over to the Chevrolet garage today to talk to my friend
    about your problem. I will let you know what he says. I tell you, I have never seen
    so much electrical problems on these Blazers and Jimmys in my life. GM has 43 technical service bullitens on them and several recalls. I'll be back...
    Thanks for your patience...
  • jlflemmonsjlflemmons Posts: 2,242
    Hey, cardoc, I assume you mean the problem steve is having. Thanks for the help.

    I know there were major electrical issues with the 2nd generation when it came out. Sometime during this generation there were some major improvements made in the harness designs that helped. But these are still one of the early generations that had a BIG increase in complexity.

    You want to see one that will really mess with your head? Check the door jamb switches. On my '02 2dr, there are no wires to them! The BCM has a remote sensor/switch inside the door that reads the latch, and turns on/off the interior lights accordingly. Bizarre.
  • cardoc50cardoc50 Posts: 49
    They call that up to date computerized improvements that a normal person would have to take it to the GM dealer to have fixed. They'll pull out a TSB and have it fixed in an hour and the fee? Ha Ha. I talked to my friend about your problem and he was nameing off stuff I've never heard of so I just cut it short and left. There are more sensors on these things than anything I've ever saw. The thing is,a sensor not related to a problem we might have can cause a slew of non related problems. Why
    would they put that in the door to turn off the interior lamps? I thought the switch
    was fine. It worked for 50 or so years! LOL. I'm going to the Ford store and trade mine in on a new Fusion. lol
  • jlflemmonsjlflemmons Posts: 2,242
    I swear the only thing I could come up with on the door switch was that they already had the hole molded in the dash endcap, and had a boatload of switches to get rid of. The first time I came across this I spent a good 15 minutes looking for the harness connector that "must have been pulled off" before I realized that all the functions were working normally without the switch connected, and then looked close enough at the harness contacts on the switch to see that they had no marks from having ever been connected.

    Very odd, and I don't know for sure exactly what year they did this.
  • cardoc50cardoc50 Posts: 49
    I need help. My 1997 Jimmy 4x4SLE will only start when you release the key. I crank the engine and it cranks normal but will not start until you release the key.
    That means most of the time it won't start because you only have a second before
    the key is on the on position. Of course the first thing I thought of is the ignition switch. It has the high output csefi engine or OBD 11 as it's called. Remember it is a 1997 year model. My question is simple...Where is the actual ignition switch on my model? I know this will sound stupid to a lot of you guys but,stupid is as stupid does! lol. Please help.The Jimmy looks brand new and I've kept it that way. I want
    to drive it again. I've even let the registration run out.(no tags) Now it just sits in one side of my garage looking pretty. If you think it's not the switch, I'll surely take any
    idea and look into it. "WHERE IS MY IGNITION SWITCH?" and to think I'm a retired mechanic with 38 yearts of service! I'm anxiosly waiting for a reply.Thank you so very much.
  • cardoc50cardoc50 Posts: 49
    I found the ignition switch on the 97 Jimmy. Of course it's by the key switch under the steering I know on most Fords they use a rod connecting the key switch down the steering column to the ignition switch mounted low on the steering column. Thanks cardoc for letting yourself know where it's located! LOL I'm not only geting old but I think the word senile may fit in there somewhere.
  • jlflemmonsjlflemmons Posts: 2,242
    Sorry I didn't see this sooner, bud, I coulda helped. What you found on your Jimmy is pretty typical on GM. Did you have any trouble getting it swapped out?
  • cardoc50cardoc50 Posts: 49
    Sorry I got you and Steve mixed up earlier. No I have'nt got to it yet. My wife's still in the hospital and I just found out my Big brother has cancer and they found it too late it's in several places and in his lymphnodes.
    My Jimmy's the year where you use a screwdriver to bend the spring away from 4 notches and then remove the horn (airbag). then I can get to the steering wheel and then the switch. Guess what the switch cost? I may have you send me some money! LOL 17.69. Seventeen dollars and change. Thanks friend. I'll let you know
    how it goes. I also heard it was a common problem on those vehicles.Thanks again
  • jlflemmonsjlflemmons Posts: 2,242
    Man, sorry to hear about your wife and brother. Seems the older we get, the more we realize our mortality. You and your family will be in my thoughts and prayers.

    regarding the switch, you're luck you are changing the cheap switch in the column. You don't even want to know what that multifunction switch on the left costs! Would you believe $195 wholesale???!!!

    And on a 2002 model, $265 wholesale!!! Needless to say, if anyone drives my Blazer and doesn't treat the switch with gentleness, I thwack them in the side of the head. :surprise:
  • Thanks for the prayers.Prayer changes things. You seem like a very good man.
    Well,I had to change the multifunction switch over 2 years ago. Did'nt have any rear lamps. The 17 dollar switch I was reffering to was just the key switch.Come to find out the ignition switch directly under the key switch is 99.00.So I cleaned and tested the ignition switch and it is fine. I put the column back together and drove it for about an hour and everything seemed fine.I think I'll put license back on it and drive it again. My 99 cavalier is ok to drive but, it ain't no Jimmy! Thanks again for your help and concern. You are a good man. TTYL
  • jlflemmonsjlflemmons Posts: 2,242
    Let's see here...

    Cavalier, Blazer. Cavalier, Blazer....

    C'mon, that's not even close! :D
  • the ignition switch is considered that entire wire cluster that runs from the column to the fuse block! Looks good, no apparent damage or burns nor loose connections, it seems. Just bad engineering or something. My Brake and ABS lights would flash in the dash simultaneously as if it the computer was performing a systems check during operation, the blower would stop blowing and the windows would not roll down. Sometimes upon the initial start-up, there would be a 2 second delay b4 the dash lights appeared and the starter engaged. All caused by the faulty ignition switch (wire harness that connects to the key ignition unit and runs down to the fuse block located in the steering column)! 90 -100 bucks

    warren caine 97 blazer
  • Yes you are right.After cleaning etc... I thought it was fine. Well it's not fine. On
    the initial(cold engine)start up,you crank the engine and it does not even try to
    fire. When you release the key,that couple of seconds that the engine is still turning from the attempt to start, it fires. After several attempts it will finally start
    on just those seconds that you release the key. After it starts(and it takes a while)
    everything is fine no dash lamps that should not be on or anything. Then you can turn it off and it starts like a new one all day.Unless it sets for a few hours4-8or so.
    I don't want to buy a 99.00 switch and it not rectify the problem. It is a 1997 JIMMY
    4.3HO with the OBDII injection.Plenty of fuel pressure and shows no trouble codes
    with my scanner or the Chevy dealership where my friend works. It runs smooth and no other problems.Your info is correct. Can you think of anything else it could be? I'm grasping for straws here. Thanks so much.
  • jlflemmonsjlflemmons Posts: 2,242
    Ouch, what you are describing sounds like a worn out contact in the switch. An ohm meter could confirm this. I checked around on the S10-Forum site (interesting group, but a few knowlegeable folks there) and found this:

    Well, I went to the library and printed out the schematics of the truck. Everything under the hood was fine, like the fusible links. Then I probed the #4 fuse going to the dash idiot lights and only had 220mVDC. So I checked the ignition switch. Probed it and had +12VDC at the main red wire but still only 220mVDC with the key on. Then I used a jumper wire and wa-la. It worked. So I find an ignition switch harness at OReilly's for $90.00. The thing is you need a special E4 torx socket to get the igntion switch out. I drive all over town and finally find one for $6.00.

    I have another online source I am checking into. The guy above was having a very similar issue to yours. Someone else posted that if the vehicle can be started, gently move the key back and forth a small amount, and see if the engine shuts off, particularly when moving toward the "start" position. I will post more when I get an answer from these other guys.
  • jlflemmonsjlflemmons Posts: 2,242

    I checked my sources and they are saying most likely ignition switch. I hate pointing at something without more definitive "proof" but they also state that for whatever reason, '97 was a bad year for ignition switches in these beasties.

    Wish I could offer more suggestions, but that is all I can come up with.
  • I agree with you. I'm going to remove my lower console today for another reason.
    I need to peel back my carpet to check the wiring that runs directly under the drivers feet.I don't expect to find anything wrong but,since I bought the Jimmy it had a small trans leak. One trans line is clean and has fluid dripping off of it. I can't get my hand up there to tighten the line up,so I may have to lower the trans just enough to tighten the line.I live in West Virginia and noticed the leak a few years ago in Daytona Beach Fla. Of course it has gotten worse over time. It looks like I may be able to acess the line from the top. If not,no harm no foul anyway.Of course if I lower the tranny a bit,I'll need to keep a good eye on the 4x4 switch and vacumn lines.I can do that from up top too. Maybe with a mirror but I think it'll be ok.
    I still think it's in the ignition switch but these are things that need looking into anyway. I've been driving it around some and boy, like I said a Cavalier ain't no Jimmy! LOL Thanks for the input. I may check voltage to the negative side of the coil when I crank it vs. when the key is on or running. Thanks friend for your input. I'll let everyone know what I find.(and then put an ignition switch in it) LOL
  • jlflemmonsjlflemmons Posts: 2,242
    While you are up to your elbows in that anyway, don't forget to check the oil cooler lines for leaks where the hose is connected to the metal part. This is the voice of experience speaking here. I kept thinking I had a leak above the cooler lines and one of the folks here let me know those lines will start leaking with age.

    how's your family?
  • As I suspected there is no access to anything by removing the console.But hey,
    it needed a good cleaning under there anyway. Why did'nt I know that from being under the vehicle before? Again, does the word senile come in there somewhere?
    LOL. I was able to remove the crossmember and push the tranny over a few inches
    and tighten the line. when you take the x-member out, the transfer case rests on a
    non removeable x-member giving you an extra 3-4 inches. So that helped too. I put everything back together and guess what? The engine threw a rod through the side of the block! Just kidding.LOL. It started up fine every time I tried. It started up this morning cold and I started it a few more times.I did however tape up a couple places where it looked like wires were rubbing on the column and a plastic shield.who knowes?Everything is good right now.(knock on wood).I'll continue to drive it as much as I can(no tags)and see what happens.That's where we are at right now.I'll keep you posted. Thanks again friend!
  • jlflemmonsjlflemmons Posts: 2,242
    On the road, again ...

    Glad you found/fixed it. Of course, Murphy's law says wait till it rains and you're in your Sunday go to meeting clothes! :D
  • Well, I told you wrong! I'm so embarrased. Another problem or maybe "THE" problem.How about the fuel filter bracket not bolted to the frame at the last change?
    Filter bouncing and vibrating wollowing out the plastic line and in turn causing it to suck air? Now also the rear metal line rubbing against the x-member of course another hole in metal line this time. I found the exact same vehicle at a local
    salvage yard. The owner gave me the lines and I cut off what I needed with a tubing cutter and attached them with compression couplings. Now all is well.I don't know why it started the other day.At least I knocked on wood(my head).First place to look huh? I going to sell it. I'm looking at the new Ford F-150 Raptor. It is a mean ride. Check it out. :mad:
  • jlflemmonsjlflemmons Posts: 2,242
    Ford Raptor I haven't looked at. I will go see.
  • It will be available with 400HP. My son has a 2009 F150STX loaded and he said the
    Raptor will also be available with 500 Horses! And of course he will get one.My
    wife said NO! So I guess I'll get a little red car. LOL Who wears the britchess
    in my house? You're a nice fellow.It's been nice talking to you, and I hope we
    will stay in touch. I hav'nt seen anymore problems come up but mine. Talk to you
    later friend.
  • Okay so none of my interior lights or the stereo work when the igntion is on and the car is running except for the eye ball lights, the mileage and gear indicator and the turn signal indicator lights (which are fully illuminated all the time but the signals still work.) This didnt seem to happen until a couple days ago when the temperature outside dropped to around 20 degrees. The stereo acts like it wants to work but cant until the ignition is off. Any help????
  • actually figured out my own problem! the antenna cord where it plugs into the stereo has a metal band around it, a ground im assuming? anyways it was cracked in half so there was no contact. touched it together and everything popped on! just gotta get a new antenna adapter for my head unit. boo ya!
  • I'm glad to see you fixed your own problem.Something so easy as a bad ground
    would be very very hard to diagnose. Other people should take note of this in case it may happen to them. I would not have guessed that the antanea ground would have caused your problem. I would have suggested a break in the circut insturment panel. I would have been wrong. Thank you for sharing the info with us. I will surely remember what you found for further referance.
  • jlflemmonsjlflemmons Posts: 2,242
    Odd, indeed. The grounding band on the antenna lead does go to the body, and to the radio. But if the ground for the instrument lights and the other lights you mentioned is going through that ground, you might want to take a closer look under the dash for another missing/broken ground.

    The lighting circuit does go to the radio to give the dimming effect for the indicators. It also goes to the lights in the instrument cluster, but the turn signal indicators do not dim. Just sort of thinking out loud here, but all these lights should not be going through the antenna lead.

    Looking at a schematic on a 98 and later model. Shows a grounding junction with several black wires, one of which goes to the lighting circuit of the instrument cluster, and another that goes to the *stock* radio connector. This may be where you are losing your groud connection, and by connecting the ground through the antenna you are feeding back a ground through the radio lighting ground to the instrument panel. You might just look around the radio, and just to the left of the steering column (if I am remembering locations correctly) and see if you find a damaged junction/splice connector with black wires in it.

    A man can go crazy trying to track down the ground loops in a modern day auto electrical system! Good Luck!
  • i have a 2001 blazer as i stop the brake pedal gets hard an pulsates back at me an the car keeps goin forward i let up it an reaply the brake an it stops. this happens at the end of the stop an there is a growling noice to the rotors are finr an i changed the booster. i had an asb lite on an when the lite went out this happened now the lite stays out an this happens every stop.
  • jlflemmonsjlflemmons Posts: 2,242
    You don't say how many miles are on the vehicle, but regardless, you have a problem in the ABS module. That vibration you feel is an engaged ABS, which will lengthen stops if activated under non-panic/hard stop conditions.

    When you first start the car, the ABS light should come on and a "buzz" should be heard from the ABS pump during this time. It is a diagnostic that runs every time you start the car. Don't mess around, get this one checked out.
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