Edmunds dealer partner, Bayway Leasing, is now offering transparent lease deals via these forums. Click here to see the latest vehicles!

Electronic Gremlins - Electrical Problems That Are Driving You Crazy

11718192022

Comments

  • kiawahkiawah Member Posts: 3,666
    Water in the light, should have caused that circuit to short out, which should have caused a fuse to blow.
  • bbpar117bbpar117 Member Posts: 2
    I have dashboard and tail lights that blow fuses at least 2-3 times per week. They both share the same fuse. The signal lights continue to work even when the fuse blows. What type of problem would cause this?
  • kiawahkiawah Member Posts: 3,666
    Someone would need to know your year/make/model, and then have electrical schematics to review.

    But without that info, I'd suggest checking the taillight bulbs for proper operation. Brake lights turn on the high intensity filament in the bulb, headlight/running lights turn on the low intensity filament in the bulb.
  • bbpar117bbpar117 Member Posts: 2
    I have a an 1984 Chrysler Fifth Avenue with 318 2 bbl carb.
  • 2000buickrehab2000buickrehab Member Posts: 11
    Hi all, I own the Regal's twin, the Century, but there seems to be more activity here than over at the Century forum.

    My Century has some issues that you may know how to resolve. The twin cooling fans will not kick on, I checked the battery because of the low voltage safety feature, had a dead cell in a <2 yr old battery, replaced, but still no fans. I can jump straight off the positive to the white fan on the right side, the second fan will not kick on even with a hot feed. See next posting for the rest.
  • 2000buickrehab2000buickrehab Member Posts: 11
    The A/C will not engage, the odometer and (PRNDL) will not display, intermittent failure of the "lock" feature on the door and via remote keyless access. is there a relay, ground or inline fuse between the power supply and fuse panel for these lines that I should be looking for?
    Plan on pulling the Cluster to look for a bad relay/resistor/fuse/bulb, but there seems to be a bigger issue. See next posting for the rest.
  • 2000buickrehab2000buickrehab Member Posts: 11
    no current on either side of the 10 Amp fuse located at Rox 4 & 5 of Column A on the fuse panel( Crank Signal, Cluster, BCM), same with the fuse located at Row 5&6 of Column A ( Heated Mirror)
  • kiawahkiawah Member Posts: 3,666
    I don't have schematics for your vehicle, but generally yes I would look for a relay. The fan motors draw high current, so there is generally a relay (or two), but I have had a Chrysler that performed the same function with a transistor heatsinked to the vehicle frame.

    You can check out the fan motors themselves, by applying 12volts directly to the motor to verify that the fan motor itself is good. Before doing that, I always (with all power off), spin the fan blade manually to make sure it's not bound up. Check also the fuse to the fans. Assuming the fans work and the fuse is okay, then you know the problem is in the control circuitry as opposed to the fan motor.

    The control circuitry differs obviously by mfg, year, make, model. I've seen a couple different logic being used on fans:
    - two fans, one is turned on by high engine radiator temperature, the 2nd fan turned on when the a/c is turned on. Computer logic turns on a relay, which turns on a fan.
    - two fans, both turned on low speed based on high engine radiator temperature (they do this via a relay, where the fans are wired in series, hence they run at half speed), and when the a/c is turned on the relay switches and the fans are wired in parrallel, hence both running at full speed.
    - one fan, controlled by logic and relay,

    I'm sure there are other valid combinations of circuit control.

    You would probably have a pretty big fuse (like 20/30/40 amps) for the fans, find that in your owners manual and make sure that isn't blown. Then check to see if the fans will work with direct power given to them. Then at that point, look for the fan relay(s).
  • kiawahkiawah Member Posts: 3,666
    You posted a bunch of other problems here, while I was trying to answer the radiator fan question. Seems like you've got larger electrical issues than the fans.

    Again, I don't have any electrical schematics for your vehicle, which you may want to locate/buy/subscribe to. I'll give you some generic things that I would look for:
    - check first that you have a good battery, should be putting out 13-14 volts, have good solid, no corrosion connections to the wiring.
    - Many vehicles will have a 'fusible link', or big chunk of metal that acts like a fuse, generally rated around 100 - 150 Amps.Think of this as the fuse to the main set of fuses.
    - There are some fused circuits, which are supplied power all of the time from the battery. Thinks like security system, lights, power door lock opener, etc. There could also be relays in this circuitry, to handle higher current levels.
    - There are some other fused circuits, which are only supplied power when the key is in the ignition and turned on. There could also be relays in this circuitry, to handle higher current levels (for instance, the key in the ignition turns on the relay, the higher current relay points provide the power to those fused circuits). Things like radios, heaters, a/c, defroster windows, etc

    When you have a number of items that are showing symptoms of electrical failure, start with your basic main battery power feeds, and verify that they are working.
  • 2000buickrehab2000buickrehab Member Posts: 11
    Pulled and checked all 3 fan relays from the fuse panel in the engine, all 3 "clicked" when powered, even bought a brand new one to cycle through, still nothing. I am going to go back and start at the fans and follow back through the connectors and harness until I start getting some current somewhere. Thank you for the assistance.
  • kiawahkiawah Member Posts: 3,666
    If you have 3 fan relays, then I would expect the logic to be where one of those relays connects the fans to be in series for low speed, and then in parallel (or direct power connect) for high speed.
  • 2000buickrehab2000buickrehab Member Posts: 11
    KIAWAH, thanks for the recommendation. I have the 3 volume service manual for the 2000 Regal/Century, straight from GM, however, I have issues with following any schematics in there becasue the first few exploded engine diagrams were mislabeled and some components completely missed. The Haynes manual has too little information to be of much assistance with this issue.
  • 2000buickrehab2000buickrehab Member Posts: 11
    New battery went in 2 days ago, was a little surprised to find the prior one to have less than 10 volts with a dead cell, it was less than 2 years old, stuff happens.
  • kiawahkiawah Member Posts: 3,666
    Perfect,

    I've always bought the factory service manuals as well for my GM vehicles. I haven't seen the problem you reference with mis-labeling, so not sure what to expect with that.
  • zoot1zoot1 Member Posts: 1
    I have a 96 Range Rover SE 4.0 ac,at,4x4 pb,pw, etc. I was haveing trouble with it being underpowered and running rough, I did an ohm check on the plug wires they were ok then did a spark test from the coils, the two of the coils on the drivers side both were bad no spark at all the after futher inspection I could see that they were heat warped. I replaced with a complete coil pack 4 coils fixed a couple Exhaust leaks put it back togeather did a test drive it died, a complete loss of power I replaced the20amp main electrial fuse went back and checked the coils again and the same ones in the new coil pack were melted down same as before and the vehical still ran rough as before ? can anyone give me some insight ?
  • sosteensosteen Member Posts: 3
    I have a 1980 Toyota Corona that has been dying on me while driving. I have replaced the ignition coil, plugs and wires, alternater, checked distributor cap and the pick-up coil. It seems to die when it gets hot or I run the A/C and will not start again for usually 15 minute, sometines longer. When it does this there is no spark coming from anything.Does anyone have any suggestions about what this could be?
  • kiawahkiawah Member Posts: 3,666
    I don't have a set of electrical schematics for that vehicle, and if it were me that's where I'd start.

    You'll have to meter out some circuits, when you have a failing situation. Verify that the keyswitch is good, any relay's that are in the circuit, eliminate any aftermarket security systems, and verify that you are getting power to the distributor, etc.

    Don't throw any more parts at it, until you figure out where the problem really is.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Hmmm...no spark with a very hot engine? I'd have to say if you're sure about no spark then you haven't checked the ignition components correctly. You might get yourself a simple spark tester to make sure you are losing spark; also you can squirt some starter fluid into the air filter when it fails to start, and if it kicks over for a few seconds, you have a fuel problem not a spark problem. What kind of voltage are you getting on the positive side of the coil? should be 12V. How about the negative side of the coil? Is that properly grounded?
  • sosteensosteen Member Posts: 3
    This is in response to the question I previously asked about a 1980 Corona with no spark. If a electronic ignition control module was the problem would it just quit or would it be intermittent? Could the ballast resistor be bad and would it be working intermittently if so? Thanks again for your help
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    It could be intermittent with regards to engine heat, yes.
  • sosteensosteen Member Posts: 3
    I got a voltage meter and tested the positive side of the coil negative to bare metal it read 12v. could not get a reading on pos to neg terrminals on the coil. the key was turned on.i got 12v on all the resister post to bare metal. is the ground wire bad or not grounded right?
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Very possibly a bad ground, yes.
  • sully20sully20 Member Posts: 1
    Just purchase an '03 Beetle - 5 speed Turbo... fun fast car. One small issue so far - the cruise control will shut off when I turn on the park or head lights...

    any simular issues or does anyone know what I need to tell the mechanic to fix.

    thanks
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    I'd suspect the stalk switch (multi-function switch) because the cruise control is shut off by the brake light switch, and the brake light circuit usually goes through the multi-function wiring. This is just a guess but it's the only tangible connection I can make in my head between the cruise control and the headlights.

    If not that, then I guess I'd tear off the fuse box and look for signs of shorts or corrosion.

    If not either of those, then lots 'o luck finding this one....it comes down to tracking wires down, by the hour labor rate.
  • kiawahkiawah Member Posts: 3,666
    edited September 2010
    You might actually look at your rear brake light bulbs, to see if a filament is broke in a dual filament bulb, laying over and touching the other parking circuit filament.

    Most cruise controls will turn off, when the brake circuit is energized.

    If the bulb has filaments crossing, it would effectively short the parking brake circuit, to the brake circuit. You turn on the lights, it back feeds and energizes the brake light circuit, and turns off the cruise control.
  • bolivarbolivar Member Posts: 2,316
    If this isn't right, it still is a brilliant deduction!!!!
    I like it!
    A shorted out bulb filament!
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Me, too. I thought it was a very 'bright' idea ! :P
  • kiawahkiawah Member Posts: 3,666
    edited September 2010
    I've shot my own fair share of weird electrical bugs, particularly when hooking up trailers. After a number of times of getting out the meter and troubleshooting and usually finding a bulb problem (short or corrosion), I just start there first anymore.
  • tannietannie Member Posts: 1
    hello,
    my mom's 2000 oldsmobile silhouette GLS has a door ajar digital light flashing on even thought all the doors are closed all the way. the contacts on the sliding doors are fine and shiny.
    Sometimes, when hitting a bump, the interior lights go on then off.
    Any help?
    thanks
  • kiawahkiawah Member Posts: 3,666
    You have to meter out each switch, including sliding doors and hatchback doors and windows, until you find which switch is making intermittent contact.
  • burdawgburdawg Member Posts: 1,524
    Also, check to see that even though the doors are closed all the way one of them hasn't developed enough play in the latch to open slightly when going over bumps.
  • pamt523pamt523 Member Posts: 5
    Not sure if this falls under electrical, but this is an intermittent problem when I can't turn the key past acc. Engine turns off, but I have to wait sometimes a few seconds to a couple minutes. I hear some clicking so I know I can remove the key and hear a little motor running sound. I've had this to the dealer twice and they don't have a clue. Getting ready for round 3 with the dealer. Any ideas would be most appreciated. 2008 Equinox - 43000 miles.
    Thank you
  • bolivarbolivar Member Posts: 2,316
    No expert on this car, but sure sounds like there is an electric solnoid in there that has to move a lever or something and it isn't electrically or mechanically working well.

    If so, a dealer should really be able to fix this problem. Don't know why they should need serveral tries, unless they are unable to replicate the problem while they have the car, and so aren't doing anything with it....
  • pst8888pst8888 Member Posts: 1
    I have several electrical problems with my van. I am wondering if, somehow, the problems all lead to the same bad part, etc. The problems don't appear to be linked to the same fuses. Is there something I could check that would affect all of these things, without disabling the van?

    gas gauge - mostly stays on full, but sometimes dips down to empty, even when tank is full
    door locks - they work, sometimes
    heater - fan blows, heat comes out, sometimes, usually cool air
    low coolant warning light - comes on, goes off, comes on, goes off, even when coolant full
    little symbol that indicates electrical problems usually on, occasionally goes off

    any ideas?
  • burdawgburdawg Member Posts: 1,524
    I doubt if one thing is causing this many widely varied problems.
    gas guage - probably a bad sending unit in the gas tank
    door locks - you didn't say if it's the door switch, remote, or auto locking, but I assume it's the door switch, which is probably dirty and carbonized from use
    heater - could be many things, clogged core, faulty control, temp sensor, loss of vacuum control
    low coolant light - probably the float sensor in the resivoir tank
    little symbol - do you mean the service engine soon or check engine light?
    Remember these are just guesses, and it's 11 years old. These niggling little problems can be expected.
  • srs_49srs_49 Member Posts: 1,394
    Could be a bad ground connection someplace.

    A loose, broken, or high-resistance ground connection could allow sneak paths for current through other circuits, that can raise havoc with indicator lights, gauges, and sensors.
  • 73chevy73chevy Member Posts: 1
    Have a 2001 S-10 & was told that the manual says to turn off the DRLs to push the dome override button. Problem now is that after initial warning bells stop I have the DRLs on but no tail/ license/ turn/ brake lights out back. Next I can hit the "DO" button again & now the DRLs are off, no headlights either, and the lights out back are now on, dimmly!! Any input is greatly appreciated!!! THANX,
    CHEVY
  • chevelle22chevelle22 Member Posts: 2
    hi there having troubles with my 93 dodge cummins. have no power getting to my fuse box that runs my park lights and dash lights, could it be a relay im missing ? everything else works great just no marker/park lights and dash lights. ran power to output of fuse side and dash lights came on so its before the fuse box somewhere
  • dhavlickdhavlick Member Posts: 2
    So im new to all this and I have a problem with my car, I've got a 2005 Toyota corolla sport. I just installed a new headunit, 1200 watt max output amp and 2 12 inch subs, and I did everything thing like I've done before but this time my front right headlight (if your looking at the car) was not working. I hooked everything up by the book. Tomorrow morning I'm going to see if the headlight just burnt out. But if it's not that what could I have done?
  • srs_49srs_49 Member Posts: 1,394
    Where did you take off the +12V for the head unit? At the fuse box? If so, that's where I would look.
  • dhavlickdhavlick Member Posts: 2
    No I just bought a wiring harness, I also grounded the head unit to the wiring harness in stead of to the body of the car. Could that have something to do with it?
  • burdawgburdawg Member Posts: 1,524
    It's possible. Check the bulb first though in case it's coincidence.
  • srs_49srs_49 Member Posts: 1,394
    I agree, check the bulb first, or just buy a replacement and try it.

    If the bulb checks out OK or the replacement doesn't work, disconnect the head unit (unplug it at the harness connector) and see what happens.

    Also, check your fuses in the fuse box.
  • maddog0324maddog0324 Member Posts: 55
    The radiator fans & a/c compressor stopped working the other day. The fuses, relays and grounds all check out. There is no loss of freon. When you select a/c on the control-head, the indicator lights but compressor does not engage. The radiator cooling fans do not come on at all. The engine almost overheated in rush-hour traffic. I can't drive this car until I resolve the cooling issue. Does anyone have any ideas?
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    which fuse block are you looking at? The ones controlling your problems are underhood, not in the passenger compartment. There's a 10 amp marked "37" that controls the AC compressor AND the Body Control Manual---so that's one suspect.
  • maddog0324maddog0324 Member Posts: 55
    The fuses that I checked were the ones under the hood. I suspect the BCM is faulty because the Theft System indicator has been on constantly for the past year. Do you have any idea how much a BCM will cost to replace? I need to get this car back on the road.
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    Well the retail on the part is about $250 bucks, with a little bit of labor to R&R, and then it has to be programmed properly with the scan tool.
  • wildflrjanewildflrjane Member Posts: 1
    Approximately six months ago, I noticed that once my car started and the running lights were on, when I turned on the heater or defroster inside the car the running lights would go off. If I shut off the heater the lights came back on. This went on for the past 4 months until finally the defroster, heater, fan,the front seat heater, and air-conditioner don't work, the interior clock does not display the time and I have been reading the forum posted here on the Grand Prix problems. Has anyone reached a reason for these issues? I need to get it fixed, but I don't want to spend a fortune for a local mechanic to try this and that. The car runs well otherwise, can anyone help me and let me know what the best fix for this problem is?
  • dfkcks913dfkcks913 Member Posts: 1
    So I am having a problem with the cassette tape adapter, I use a cassette tape that allows you to hook up your iPod to a wire that is connected to it, for some reason, when I put the cassette in, it makes a sound like its searching for something (rewinding, forwarding) and plays the iPod for 1 sec. And then automatically ejects it. I am tired of this!! If ANYONE can help, please help!
  • Mr_ShiftrightMr_Shiftright Member Posts: 64,481
    The cassette itself is probably defective. Try another adapter.
Sign In or Register to comment.