Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Cadillac DeVille Electrical/Lighting



  • dtstldtstl Posts: 1
    This is a complicated discription of my problem, so I'll jump right into it. As you read this, keep in mind that my back-up lights NEVER work.

    My brake lights work properly when the headlights are off. All three of them come on, and no bulbs are out.

    With the headlights on:
    When I turn my headlights on, the third brakelight (above the license plate) does not work. The license plate lights are extremely dim, not really illuminating the license plate at all. The light-up pattern of the taillights is different also. The entire taillight is lit, except for the lower inside quarter of each taillight (not applying the brakes). When braking, they light up properly, and they blink properly with the blinker on. If I disconnect the third brakelight, the normal taillight pattern comes back (a thin stripe on the outside edge of each taillight), but all other problems remain.
    The trunk courtesy light is always dim. When it is removed, the license plate lights go off. The license plate lights also go off when the trunk release is disconnected.

    It seems to me like the trunk is not getting the proper voltage to carry all the lights.

    1. Replace the wiring harness in the trunk (Grounded by the left taillight)
    2. Replace the headlight switch
    3. Replace the dim bulbs and see what happens.

    Also, could the traction control be carried on the same wiring through the trunk? Because when this started, the yellow traction control light comes on in the instrument panel periodically. I can't pinpoint what is triggering it though. When that light is on, I cannot manually disengage the traction control with the button on the center console. This could be a separate problem though.

    Can anyone help me, or direct me to someone who can? The car can't pass inspection without the third brakelight and backup lights.
  • bolivarbolivar Posts: 2,316
    Sounds like a ground problem in the rear light circuits.
  • mbouchardmbouchard Posts: 1
    I have a 99 caddie in the shop now. Electrical problem with power being drained overnight, or if car left sitting for more than 8 hours. Sometimes the trunk and gas cover pop open when car is started.

    I'm at a loss as to what could be wrong. Have you received any good directions what to do with your problem? I won't drive until I am sure the problem is fixed.
  • himihimi Posts: 1

    I´m new here so sorry if I´m posting in wrong forum.

    I own a Seville 1991 V8. There are two fuses under the hood named INJ (Probably Injection?) of 7,5 A each. One of them are very often popping which makes the engine only perform 50% of it´s capacity according to my experience.

    Any ideas of where to start analysing the problem?

    Kind Regards Himzo
  • okko1okko1 Posts: 327
    would agree sounds like ground problem see the same thing in trailer lights. will likely be wire harness or light board contaminated with water check lense some times evidenced by green color
  • okko1okko1 Posts: 327
    the more you tell the more it sounds to me like that wire harness is cut or pinched somewhere have you had the seats out or installed anything in the truck
  • shemikashemika Posts: 1
    I got new starter put on two days ago and now it wont turn over at all. I was told it could possibly be aneutral safety switch. could this be true and if not what do you think it is? :cry:
  • smilingjoesmilingjoe Posts: 5
    The battery is not charging. The mechanic has taken the alternator apart and found all parts are working, then re-installed; yet, it does not charge the battery. The batttery is o.k. This is a Cadillac 2000 DeVille with the Northstar engine and only has 65,000 miles.
    Any help would be appreciated.
  • okko1okko1 Posts: 327
    the alternator is internaly regulated if he did a bench test and it showed a 14 volt 70 amp cycle may be 12 volt source may have a problem some models have inline fuseable links some have charging system relays and fuses check these
  • smilingjoesmilingjoe Posts: 5
    Thank you. Will have mechanic check it. :)
  • I have a 1999 Deville and the turn signals stopped working. When you turn the left on it is just stuck. Same with the right turn signal. I checked the bulbs and replace to fuses. I bought a flash fuze from the dealer,but can't find where to plug it into. Anyone have this problem or know how to fix this. My other cars, I just replace the light bulbs and flasher and this fixes it most of the time. Please help.
  • etbartleyetbartley Posts: 2
    I just bought a well taken care of 99 Eldorado last Friday and as of Saturday it started doing this! The starter makes a strange clicking noise, the battery shows like 10 volts, then the clock and onboard diagnostics reset themselves (but strangely my saved radio stations are "remembered") and sometimes the trunk and fuel door will pop open. I replaced the obviously stock battery on Saturday with some Bosch upgrade, and it ran fine for 3 days. Today, it started doing this again! The guys at work jump started my car and I drove it home and it was running fine, with a battery voltage of about 13.0-13.5. Once I got home and turned off the car, it wouldn't start again, and the voltage dropped to like 9.5 then 8.5 until I gave up. I jump started the car again and drove it to Pep Boys and had the alternator, starter and battery tested and they are fine but they said the NEW battery, which is less than 3 days old, has a bad cell. I don't know what the chances of this happening are, or if something wrong with the car destroyed the new battery, but I'm hoping (praying) this third battery will work! Did you ever figure out what the deal was with your Cad? I see you posted this in May, so maybe the problem has been diagnosed by now, I'm just trying to save myself a bunch of hassle and headache of having a dealership or mechanic guinea pig it to try and determine what the problem is. Any info you can provide is greatly appreciated!
  • After sending the alternator out to an expert, it was determined it had to be replaced. An internal part had burned out. As they are water-cooled, the total cost was $1050 CDN. The alternator is in an extremely difficult position to reach and my mechanic of 25 years charged me almost no labour. I hope this is not the case with your unit. :sick:
  • bolivarbolivar Posts: 2,316
    Well, if the battery has a bad cell, it needs replaced, new or not.

    If this problem continues, I would guess the problem being the battery cables, the positive or negative. Corrision has probly gotten inside the rubber and eaten almost thru one or both. A common problem on Cadillacs.

    The positive cable is somewhat complicated and expensive to replace completely. It will go from the battery to the starter, which on a Northstar is inside the intake manifold. Intake must be loosened and lifted to get to the end of the positive cable.
  • sassy13sassy13 Posts: 1
    I was given a 1986 caddie (DeVille or Devil of a time) and among other problems its gas gauge does not work. The display on the heater or any of the other digital displays will not read out. I am having a new problem now with the battery. I goes dead very couple of days. I can hear something clicking and checked under the hood. It is definitely a electrical component. It is right behind the battery and nothing in the manuals suggest what it might be. I am getting gas fumes when I start it. It is running too rich and will blow a little black smoke sometimes. I am sure there is more to the problems with this thing. I am trying to fix it one thing at a time. I replaced the fuel filter, battery, spark plugs, distrubuter cap and roter. It does run, but runs out of gas a lot. I have trouble with the cars idle speed. I can get it right and in a few days it is not running right again. Any suggestions on getting the battery not to run down or how to get the gas gauge working again????
  • avidusavidus Posts: 2
    Every now and then, like months apart, the interior lights, cigarette lighters, and trunk light stop working. We have checked all the fuses and they are all fine..but cant find out why I suddenly lose the inside electrical overhead lights, cig lighters and trunk light. Then, as strangely as they went out, they come back on. But it's a real pain when they go lights at night, no power in the outlets and no trunk light....ARGH........any clues out there???
  • If your car has battery run down protection, it might be turning them off to save the battery. I've had my trunk light do this when the trunk was open for a long time. Then it comes back on a little later. 2005 Deville.
  • avidusavidus Posts: 2
    No, I wish it was that simple. The lights will go out for months at a time and wont come back on at all, except bu surprise, the whole thing works great, so nobody can figure it out. It must be a short somewhere but dont know where.If I plug in a jumper box into the cigarette lighter, then the lights work, so they must all be on the same circuit and not getting power from the car battery. But I have checked the fuses and they are all fine. So I just dont know...
  • bolivarbolivar Posts: 2,316
    Has someone put a trailer light package on the car?

    Has someone put an after market radio on the car?

    Has someone put an after market alarm system on the car?

    Has someone put a remote start system on the car?

    Any of these has a high possibility of messing up the electronics on a Cadillac, or any other vehicle.
  • Just an FYI - a few days after posting this I found out all of my problems were linked to corrosion on the positive (red) battery terminal. I took it to a service station and they replaced the tip (not the entire cable) and it's been working fine ever since! Of course, I have a (second) new battery now, one w/o a dead cell. I wonder if this problem killed the first new battery I got. Well, I hope this info helps someone if they have a similar problem!
Sign In or Register to comment.