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Chevy S10 - GMC S15 and Sonoma Electrical Problems

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Comments

  • philscbxphilscbx Member Posts: 33
    First.

    Take the Battery Out.

    While your messing around, put battery on charger, so it's at max output when your ready.

    Use jumper cables from battery back to vehicle to make tests as you progress as battery is charging.

    With the Battery OUT of vehicle.You can see where the cables go.
    Make necessary repairs to battery tray if in rough shape.

    You also may have inherited someone else's nonsense.
    I've seen some pretty Ugly results of what some people do,

    Look at the ends of cable very closely.
    REPLACE them if they look shabby at all.
    In other words, IF they don't look like new at both ends. Ditch them.

    IF the cables are long enough, CUT off the Garbage, and remake new ends on them. SOLDER the new ends on if possible.

    If you see corrosion going deep down into cable ends for several inches, then toss them.

    Brand New Vehicles Came with dual lead ground cables for 20 years.
    LOOK at where this smaller CABLE branching off from Battery ground is attached to. This is usually the Radiator CORE SUPPORT. If it's been replaced correctly.

    IF NOT_ THen ADD a ground wire of #10 Gauge Wire [MINIMUM] to the GROUND at Battery to the CORE SUPPORT.

    The alternate to using #10 wire is it's about 1/8" thick copper core.
    Use wire with larger copper diameter, not smaller.

    In a desperate pinch, one could use the stiff house wire for a temporary fix, but it's too stiff, and road shock will break it.

    Fasten an EYE on both ends of #10 new wire, and use the correct size for the battery bolt.

    Using a #10 self tapping hex head sheet metal screw mounted in cordless drill with hex head driver that fits screw, drive it into the back side of CORE SUPPORT.. This is the frame work holding the headlights and radiator.

    Use a washer under bolt to the connector. Apply grease to connector before attaching to CORE support

    The reason I mentioned in last post to make more than one ground wire of #10 wire attached to battery IS,

    to provide a solid ground from one panel to the next.

    Other points as well to include are the Engine Block, Firewall, etc.

    MOTOR mounts can be a huge issue of blocking a good ground back to the body and frame.

    You can also continue a second ground from CORE Support back to the engine. This un-clutters battery connector.

    Usually the best spot on the engine is the alternator bracket, or something similar.

    Make sure the movement of engine does not wear on the wire, or too short.
    Now near the back of the engine, make one going to the fire wall.

    NOW, your fully grounded up front.

    If the vehicle is rusty in general, then you may have to run a separate ground all the way back to the tail lights for example.

    One wire looping from light to light, like you would do if it was a Utility Trailer.

    Examine the headlights ground wire to make sure it has a good path.
    This wire from plug on back of bulbs could also need to be remade.
    I usually just purchase new head light plug pig tails. Cheap Part.

    This step can also help boost the alternators output as well.

    Use wire ties to keep things neat and prevent unnecessary damage from sharp edges.

    Murphy's Law will be right at your heels, so you will have to out smart him at every step.

    Might be over kill and winded for some, but some will only have to do it once.
    Later, Good Luck
  • philscbxphilscbx Member Posts: 33
    Post disappeared, what ever.

    But if dimmer is bad, and very common, they are sorta expensive and totally a pain to install.

    Auto Zone rents out the tools free to use.

    You'll need the steering wheel Puller for one and the Snap Ring compressor tool as well, or you will swear words that are heard for 5 miles.

    GM never could make this switch from day one correct.
    I have the same one in my Caddy as well. And this was a severe pain with tilt, telescopic column.

    I was forced to remove the entire column out of the car.

    I have a 35 year old Volvo 164 where the dimmer on the column still works perfect. People talk with this lever vs the horn.
  • dan120dan120 Member Posts: 3
    so you think it could also be my dimmer switch. why would it be that and not my light switch. my dimmer runs fine i think it doesnt give me problems but is that why my lights would go off sometimes..... im very confused please help. :sick:

    Thanks,
    Dan
  • mags468mags468 Member Posts: 10
    I have a 95 sonoma 4x4 reg. cab ,my headlights are so dim its like my parking lights are brighter. I put h4 high reflective bulbs in, no help. I tried taking out the day time running light modual, no help.I have checked all the grounds and even added a few ,still no better. I am hoping some one can help, it would certainly be appreciated. thanks mags468
  • gonogogonogo Member Posts: 879
    What voltage are you getting to the bulbs, sounds like a resistance in the circuit.
  • mags468mags468 Member Posts: 10
    thanks for your reply. i'm getting 12.4to12.7. i also ran pos. & neg.10g direct from the batter to see if that made a differance, none. witch would tell me it would be the lights, but they are silverstars witch are one of the brightest. its got me stumoed.
  • xwizofozxwizofoz Member Posts: 3
    My Blazer, at least once each winter has an electrical problem with the brake lights. The brake lights for some unknown reason will not shut off, even without pressure on the brake pad or when the vehicle is shut off. If you are not paying attention, it will lead to a dead battery. Is this an isolated case with my vehicle or is it systemic with S10s that year? What is the corrective action if any?
  • mags468mags468 Member Posts: 10
    Sounds like your getting moisture in your brake light switch. locate your switch and spray it with some w-d 40, that should help keep the moisture out. I hope this helps, mags.
  • xwizofozxwizofoz Member Posts: 3
    My Blazer, at least once each winter has an electrical problem with the brake lights. The brake lights for some unknown reason will not shut off, even without pressure on the brake pad or when the vehicle is shut off. If you are not paying attention, it will lead to a dead battery. Is this an isolated case with my vehicle or is it systemic with S10s that year? What is the corrective action if any?
  • moholtmoholt Member Posts: 1
    I have a 1998 GMC Sonoma 2.2 ltr. 4 cyl. auto that I need to replace the throttle position sensor on. I wanted to know if it is hard to do, and how to do it?
  • mags468mags468 Member Posts: 10
    Well this is to let everyone know these supposedly HI! OUTPUT!! lights are only 5% whiter, not brighter. What a wast of $100.00. So don`t get scammed like I did. Thanks for this sight Mags.
  • sjj62sjj62 Member Posts: 2
    Where is the turn signal flasher located on a 1997 GMC Jimmy 4WD? I bought a replacement turn signal flasher ( a round plastic module with 2 prongs) but have no idea where or how to replace it. I checked under the dash on the driver side but have no clue where it goes. I see a black plastic module with all of the wires going into it but don't see how to access it or how it comes apart or if the flasher even goes in there. I checked in the glove box and under the dash on the passenger side as well.
  • mags468mags468 Member Posts: 10
    sjj62 the turn flasher is behind the knee panel just about above trans. you will have to remove the panel to find it. good luck mags.
  • jbushee007jbushee007 Member Posts: 4
    Check under the hood, most GMC's and Chevy's have a large fuse box under the hood that contain the large fuses.
  • kdhoover39kdhoover39 Member Posts: 1
    I have a 1991, S10. I turned on my radio, it went dead like it didn't have enough power. I push my horn and it sounds like a relay behind the dash is buzzing, the horn does not honk. My dome light wont come on when the door is open but it will slightly light up when I push the horn or cigarette lighter in. Is it possessed? Or is there a simple solution to the problem?
  • john222john222 Member Posts: 2
    I have a 95 Chvey Blazer that keeps blowing the 20 amp fuse for the dash board panel. Half the gauges go along with the speedometer and if running at night with the "lights on" indicator buzzes continuously. However other important operating functions that also stop.is proper transmission shifting, and direct charging of the system by the alternator. If this fuse blows the car runs only on direct battery power. This issue seems to happen only during cold or wet weather or when the engine is cold. However if I idle run the car warming it up, for a while hopefully, without draining the battery I can put a new fuse in and it won't blow and the car runs fine. Brought it to a Chevy dealer and they too are at a loss. Thanks
  • sjj62sjj62 Member Posts: 2
    Are you talking about the lower trim panel just above the trans in the middle if the dash just below the AC controls?
    Or the panel on the driver side under the steering wheel?
    The 97 Jimmy has the automatic trans shifter on the floor between the 2 seats. Just in front of that on the dash is the cigarette lighter and utility outlets with the AC above that and the radio above that. When you remove the center lower dash panel you get the plastic vents from the heater right behind it and the lighter.
    I must be blind because I just can't seem to find the turn signal flasher for the life of me.
  • mags468mags468 Member Posts: 10
    The turn signal flasher should be just to the left of the cig. lighter . There will be 2 canisters side by side. Thats where my 95 is & Chilton does not make any refferance to any differance with floor shift or air. So to my best knowleged that is where it is. mags
  • mickeymouse2mickeymouse2 Member Posts: 161
    Obviously there is an amp spike or short intermintant. The easiest to check first and most likely the cause is the alternator. Even though it is charging, there may be an intermitant short at the internal regulator. On your alternator there is a plug with some small wires leading to it. Next time you think that the fuse should blow, disconect that plug to your alternator prior to starting the vehicle. This will turn your check engine light on and prevent charging, but its just a test. If the fuse doesn't blow, I would be very suspicious of an intermitant short in the regulator. Ok, try this a couple of times. Don't reconect that plug until the engine is off. By the way, is this fuse #4 20amp ? If this doesn't work, post more info such as engine size, production date, fuse # location, auto or manual trans, and I'll give you some other ideas you can try. Good luck.
  • john222john222 Member Posts: 2
    Hi Mickeymouse2:

    I just wanted to add one bit of info. The fuse will blow when I turn the key to the first notch that sets the panel lights on (i.e. check engine light,air bag seat belt light etc). Also the problem is intermittent and doesn't happen all the time cold and wet weather seem to aggrevate the problem otherwise everthing works fine.. The Chevy dealer is at a loss! Can this still be an alternator problem?? Yes it is fuse #4 Gauges. Auto Trans 1995, 4.3 liter voretec V6. Thanks
    John
  • hoffmanmhoffmanm Member Posts: 1
    i own a 1995 s10 zr2 and one of my inline fuses burnt up nad now my heat,windsheild wipers,and raido wont work and also my brake light and abs light wont shut off in my dashbord. iv tryed replacing the wires but as soon as i connect them they just burn up again i think its a ground problem but thats where my knolage stops ......any advice on how to fix this please its winter in mighigan and that truck is my only transportation
  • mickeymouse2mickeymouse2 Member Posts: 161
    Not sure how competant you are, but here are some things you can try. I'm assuming that this is a fusible link, not wire that is burning up. You have a dead short. If it is a fusible link, the amps are very high to burn it up.

    You were not clear on fuse number, location, or if it is a fusible link or not. Here's some advise. What ever is on that circut, that you know of, un plug it. There may also be something like a cigerette lighter or dome light that isn't even mentioned on a wiring diagram connected to that circut. Your ABS may also be part of that circut, unplug the plug at the ABS unit. If the circut that is shorted is a 30amp or less, purchass a 30amp circut breaker and wire it in for temporary testing. If the circut breaker trips whith everthing unplugged, it is either shorted wiring, or something that is on that circut you don't know about. Recommend an auto electrical shop at this point. If your lucky, and the problem has gone away with the various devices unplugged. Start plugging them in one at a time until the short re-apears. You have then isolated at least what system is causing the problem, and can either leave it unplugged, or trouble shoot it from there.

    From the things you mentioned, most common are a shorted ABS unit, shorted blower motor for the heater, or a shorted cigerett lighter if it is on that circut.Good luck with it.
  • 96sonoma96sonoma Member Posts: 2
    Hello all,

    I have a 96 sonoma v6 and i was leaking antifreeze from my intake manifold gasket.
    I pulled everything out of the way and put a new gasket in myself and put everything back. the problem now is i have no power! When i turn the key i dont get any dash lights, not even the interiors work. It is like no power is going through it at all i cant start the truck or anything its dead. i have checked all the fuses and they are all fine and he battery and alernator are new :cry: . Someone please help me out. Thank you
  • mickeymouse2mickeymouse2 Member Posts: 161
    Check for the obvious first;

    Battery fully charged, connections good, positive and negative. Now what may have happened is there are some fusible links connected to the positive post on your starter that may have been pulled loose during removal of the manifold. These power your ignition switch amoung other things. The wiring harness runs down your firewall between the manifold. During your repair you may have pulled them loose. You need to verify that power is going through those all the way up the harness. Down on your starter, the positive post has the positive battery cable connected to it, and also some other 10 guage fusible links. Those fusible links are connected to 10 guage wire, usually red, orange and yellow wire that makes part of the harness. The fusible links themselves are only about 6 inches long. Make sure the wires they are connected to have power to them. Fusible link is tricky, they may look ok, but you have to test it with a test light. Check that then repost. Good luck.
  • 96sonoma96sonoma Member Posts: 2
    Thank you! problem fixed!
  • bigmikeydbigmikeyd Member Posts: 1
    i need help i have a 95 gmc sonoma with a 2.2 in it and all my dash lights are very dim except to seatbelt light my gages dont work, brake lights and turn signals dont work but my headlights and hazard lights work. my fuel pump doesnt kick on and it will crank over but wont start. i checked fuses , batt cables, relays . i think it might have a bad ground but it has a ground to batt to engine,engine to body , and body to batt. im running out of opions please help me :cry:
  • gonogogonogo Member Posts: 879
    Check out ignition switch at base of column, not key switch.
  • jimmys10jimmys10 Member Posts: 1
    I have a 95 S10. Experienced a power failure that seemed like Alternator and car died. Removed altenator and battery, both battery and alternator check ok. With full charged battery, car is dead, no power anywhere.

    What are likely causes.
  • gonogogonogo Member Posts: 879
    Buy a 12 volt test light and start testing. The battery positive should go to the starter, every thing feeds from there.
  • blackhawk1942blackhawk1942 Member Posts: 4
    i got a 1995 chevy s10 2.2 that i bought off of a friend. it stopped running on them and they messed around with it alittle...then i got it...put a new sending unit, fuel pump, but there is no power going to anytthing in the fuel area....there is a orange wire that goes to the oil sending unit and when we tested it,,, it had very little power almost none....that goes for the rest of the truck..map sensor... could it be the pcm? the relay in the glove box clicks each time you turn the key to on....what are the rest of the relays for? :mad: if you pour starting fluid or gas down the air intake it will run and then it runs out of gas and stops....
    Any ideas? im about to loose it with this truck......thanks
  • gonogogonogo Member Posts: 879
    Check out the ignition switch at the base of the steering column, not the key one. A known problem area.
  • mickeymouse2mickeymouse2 Member Posts: 161
    Let me explained how the system is powered so you can trouble shoot it from there. Upon turning the key on you get a 2 second prim. The PCM powers up the relay for about 2 seconds until it knows the engine is running. If your not getting any power at all back at the pump, I would check the power to the relay. The relay is usually located on the firewall engine compartment passenger side. Your year and model requiers a ground signal from the oil pressure switch to keep the fuel pump powered up. I don't think this will be your problem though. The symptom of that is usually a start up for about 2-3 seconds then dies. What is common is the battery power to the fuel pump relay that is tripped when the PCM sends power to the relay. So you have to first verify PCM power when key is turned on at the relay, and battery power. If battery power is missing it is most likely a fusible link.

    One method of testing you might try, I doubt you have a power probe so you can temporarely run a fused wire from the battery all the way to the necessarry wire to power the pump. GM the wire is usually a grey wire in the harness going to the pump. Be sure to either fuse or use a 12v circut breaker rated at 30amps for this test is case your dealing with a short of some kind. If the vehicle runs after this test, its just a matter of finding out why it is not getting power.
  • blackhawk1942blackhawk1942 Member Posts: 4
    ya theres power at the relay and we replaced the relay, it clicks each time you turn the key. i use a meter to see if there was power so im good there. also we ran a jumper wire from the battery so the fuel pump and the fuel pump ran and built pressure but it still wouldn't start....could the ignition module , pcm , or anything that controls the fuel injectors stop power? thanks
  • bradenbbradenb Member Posts: 1
    I have recently replaced the head gasket on a 1997 Chevrolet S-10. Now there is not any power when the key is turned on, for any lights, or any accessories. I have used a circuit tested and determined the frame and engine are correctly grounded to the battery. I have also been able to short out the solenoid to get the starter to turn the engine over. One of the other two positive cables from the battery is securely to the alternator. The other cable has been traced to the ABS pump. The circuit tested shown a good power supply to the pump, but I can't find a branch off of it for the rest of the truck. I also had the battery tested, and it showed to have a 100% charge.

    Does any one have any suggestions? I have spent a lot of time trying to find the in line fuse that is blown, or the connection that has come loose. Thank you.

    :sick: :confuse:
  • mickeymouse2mickeymouse2 Member Posts: 161
    1997 was one of the transition years for electrical protection for GM.

    Sounds like a fusible link or blown maxi fuse. The power to your ignition switch is feed by some 8-10 guage yellow and pink wire at the switch. Those wires run through a harness down to to positive post on your starter. There are some fusible links that are connected to those wires that then connect to that positive post. Fusible link is tricky. It looks like wire and may appear ok, but you must test to verify power is going through the link to where it connects to the regular wire leading to your switch. GM usually runs this harness down a metal tube that is between your firewall and engine. Obviously you have power to the starter. So, find those 3-4 wires [fusible links] comming off that positive post on the starter and tug on them gently to see which wires they are connected to up by your firewall. Test those wires for power up by the firewall with a test light[usually yellow and pink wire]. If no power, replace the fusible links.

    If you have a power distribution box under your hood, there is a chance that it is a blown main maxi fuse. It really depends on the type of circut protection that was used on your vehicle. If you don't have a second fuse box in the engine compartment, then you have the fusible link design that GM used going directly to your ignition switch.
  • blackhawk1942blackhawk1942 Member Posts: 4
    there is 2 ground wires coming off of the negative battery terminal, find where they go and clean them, make sure the surface they are getting bolted to are clean too, i did this and my headlights and everything were tons brighter and everything worked..hope this helped
  • mickeymouse2mickeymouse2 Member Posts: 161
    You need to troubleshoot to find out what all is missing.

    Here is what you need for the internal combustion engine to run;

    Fuel, not contaminated, fuel pressure.

    Power to the injectors, key on, dash lights on. During cranking they are saturated{pulsed by the PCM} PCM uses info from cam sensor to pulse injecters as long as a ground signal is found by the oil pressure switch[some models].

    Spark to each plug, 30-40kv I think is the spec

    Compression, engine timing and air. Find out wich one you are missing and go from there with a repost.
    Your original post you stated that you were just missing power to the fuel pump. If you have multiple systems that are not getting power, its probably a fusible link or ignition switch failure. You need to test for power to the injecters, test for their pulse , power to the coil and or spark. Test these for power and function and repost.

    I dont know what tools you have but you need at least a test light and fuel pressure guage.
  • jessi29jessi29 Member Posts: 2
    I had my oil changed at a mr.lube since I did'nt feel like getting dirty and what not. After the service was done I left everything was working great until I tried my signal lights. Nethier side worked (even the blinkers in the cab) but my hazzards still work as if nothing was wrong. I went back to mr.lube and they just told me that it would have been nothing that they would have touched to cause this. I checked the fuses and all are fine (backup and turn light are on the same fuse), I'm guessing a loose wire or ground but I have no idea where to begin looking, any suggestions?
  • mickeymouse2mickeymouse2 Member Posts: 161
    Most likely its a bad flasher.
  • jessi29jessi29 Member Posts: 2
    Where would I find the flasher at?
  • junior88junior88 Member Posts: 2
    I have a unique problem that no shops have been able to figure out as of yet. It has a 4.3 with a 135,000 miles. I have replaced the distributor,cap,wires,plugs,throttle position sensor,and numerous other parts in the ignition system. The problem is when driving under load the the rpms flutter a little and there is a clicking noise from under the hood or under the dash. If I floor the throttle this issue goes away. It is setting a p0300 code and also showing cylinder 6 misfire. It used to stall out when this happened, but I fixed the stalling issue thanks to a G.M. T.S.B., that was for an internal ground that had to be bypassed. Any ideas or help with this issue would be greatly appreciated.
  • blackhawk1942blackhawk1942 Member Posts: 4
    well we replaced a few parts and we have power everywhere exept to the fuel pump...we replaced the relay but still nothing...could it be the oil sending unit? and theres power to the relay but none to the fuel pump.....cry cry lol but it would be great it i could get this truck running...... thanks for any info you can give me
  • s10freeks10freek Member Posts: 1
    For everyone whos cluster lights are out if you have replaced the factor cd player the problem is your dimmer switch the new CD players and Satilite radio transmitters blow the switch. if you still want a custom deck there is a factory line conecter you can get to fix the problem before it happens the only place i have found the conecter is at wal-mart
  • 97slammed_s1097slammed_s10 Member Posts: 1
    i have 3 different problems the first is i have no dash lights on the heater and ac area the second is my gas gauge shows full all the time but i have ran out a couple times so obviously there is a problem the third is there is a ticking sound that actually sounds like a cigarette lighter popping it seems like it is coming from under the dash if anyone can help PLEASE let me know
  • fepjrfepjr Member Posts: 3
    i've got a 99 s-10, died on the way home,had it towed, checked the fuel pump replaced the fuel filter, new alternator, new starter and battery,
    nothing leaking, when i start it the battery gauge goes normal, and the fuel gauge works, the oil pressure gauge and the temp don't which sounds normal when not starting.
    turns over fine, but just doesn't ignite
    any ideas?????
  • mags468mags468 Member Posts: 10
    fepir i might be confused are saying it wiil or won`t start? if it won`t it may be a inline fuse from the alt. or down to the starter. let know mags.
  • fepjrfepjr Member Posts: 3
    mags, it will not start, it has a brand new alternator and brand new starter on it,
    it seems to turn over without any problem, it acts like its not getting any gas,
    just keeps turning over,
    i changed the fuel filter and checked the fuel pump while i had the fuel line off and the pump was working fine

    thanx
    frank
  • gonogogonogo Member Posts: 879
    Will it start when you spray carb cleaner in the intake.
  • fepjrfepjr Member Posts: 3
    that hasn't worked, either, have tried everything that i know
  • gonogogonogo Member Posts: 879
    So you are saying with spark and fuel no start.
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