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E30 turn signal lights - weird behaviour

Discussion in 'E30 (1984-1993)' started by az3579, Apr 17, 2009.

    • Member

    az3579

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    My front turn signal lights are behaving quite strangely. Most of the time, both of them light up when the lights are on. I turn on the right turn signal, it blinks fine, but it's very dim. The left side light is on bright, but when I turn the signal on for left, it doesn't link at all. From the inside of the car, when you signal left, it clicks at a normal speed to start with, but gradually the clicking increases in speed, but not as fast as though the light was out. (Hopefully you can understand this) With the hazards on, the right-side blinks (dimly of course) and the right side doesn't blink at all.

    The rear turn signals at the moment work fine, but at times the left side one doesn't work. I have to get out and give the light a few hard taps with my hand to get it to work. This hasn't been the case recently as it has been working, but now the fronts are giving me grief.

    I disconnected the wiring harness to the turn signals and reconnected them, but it's still doing it. The bulbs are obviously fine as both light up, but I can't figure out why the front left signal won't blink and why the right side is so dim. I swapped bulbs to figure out why it's dim and even with the left-side bulb in the right-side housing, it is still dim. WTH??


    I have attached a picture:
    [IMG]

    mac townsend guest

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    sounds like bad contact

    try cleaning the bulb base and the contact/ground in the socket. some really fine emery cloth works.

    that's what I did and it worked
    • Member

    az3579

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    Emery cloth?? What is that?

    I tried to scrape some gunk off the contacts but that didn't work. Besides, the contacts for the left turn signal are pretty much flawless; nice and shiny. The front light doesn't work when signaling and it's ANNOYING! I HATE that fast clicking... :(
    • Member

    Brian A

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    Emery cloth is like Crocus cloth except a lot coarser.

    If it really is just corrosion on the bulbs, usually people remove it with steel wool (even an SOS or Billlo pad works).
    • Member

    az3579

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    I don't think it's corrosion as it looked pretty clean, but I will take some steel wool to it tomorrow as I do have some of that. It's probably one of those "well whaddya know" things.
    • Member

    Brian A

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    Good luck. I doubt its corrosion too. Electrical issues are such a pain. Since one side is shorting to the other, I'd bet its relay or switch related, but I have never diagnosed or repaired my turn signal system.
    • Member

    az3579

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    OK, I tried scrubbing some "corrosion" but it has not remedied the issue. What I did realize is that the left turn signal not "signaling" only happens when the lights are on. If they're off, they blink normally, but not as bright. This is so strange....



    I think it has something to do with my aftermarket headlights (I know, I hate them). The wires broke off the connectors so I just have them connected with alligator clips. The angel eyes are wired to be on with the parking lights when the lights are on, so I think there's something related here...

    Once again, anyone have any smileys they wanna get rid of? lol
    (non yellow ones)
    • Member

    az3579

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    OK, I've investigated my headlight wiring, thinking it might have something to do with it. I would think this because they're aftermarket "angel eye" headlights (stay away from them, BTW) and the angel eyes are hooked into the turn signal lights. Well, my current report is as follows:

    No cigar.


    I took out the headlights completely and the turn signals still won't work properly. I've made a chart to make it easier to understand what happens and when.



    * All oddities that should not be this way are in bold.
    * For the HAZARD LIGHTS section, a light is not supposed to be "illuminated", but it is supposed to "signal", so a 0 in the "illuminate" field is normal. "Y" is normal for the "blinking" field for the Hazard section.

    KEY

    ALL LIGHTS OFF = L0
    PARKING LIGHTS ON, LOWBEAMS OFF = L1
    PARKING LIGHTS ON, LOWBEAMS ON = L2
    PARKING LIGHTS ON, HIGHBEAMS ON = L3
    HAZARD SWITCH ACTIVATED = H

    IF THE LIGHT DOES NOT ILLUMINATE, = 0
    IF THE LIGHT ILLUMINATES, = 1

    IF THE LIGHT DOES NOT BLINK WHEN SIGNALING = N
    IF THE LIGHT BLINKS WHEN SIGNALING = Y

    TABLE

    Driver's side turn signal marker:
    L0 ----> 0 / Y
    L1 ----> 1 / N
    L2 ----> 1 / N
    L3 ----> 1 / N
    H -----> 1 / N

    Passenger side turn signal marker:
    L0 ----> 0 / Y
    L1 ----> 0 / Y
    L2 ----> 0 / Y
    L3 ----> 0 / Y
    H -----> 0 / Y


    So, what else can anyone come up with other than "clean the bulb socket"? :(
    • Member

    CRKrieger

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    Look carefully at the ground contact in the socket*. It can become bent and shift slightly to a point where it does not make good contact. When that happens, the lamp will seek another path to ground, producing some weird effects like those you are seeing. Bend it back and be sure it protrudes into the bulb channel enough to make good contact.

    * Unlike many, if not most, automotive bulb sockets, these are plastic and depend on a ground contact instead of socket contact, for a ground.
    • Member

    az3579

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    Based on the suggestion of someone on another forum, I checked G200 ground point on the driver's side fender in the engine compartment and the ground appears to be intact and not corroded. Quickly went over it with a wire brush to get any dirt and such off but there was none. Tested by removing ground to see what would happen and as expected, nothing happened, so when put back, everything acted the way it did before (worked, but in a funky way).



    Are you talking about the ground "pin" in the bulb socket? It looks to be intact and doesn't look deformed in any way (this applies to both sides). If it was bent, it would cause intermittent problems, wouldn't it? If so, this doesn't explain why both the turn signals blink when all lights are off, and why the driver's side turn signal blinks quickly despite both front and rear blinking at the same time. The speed of the blink on that side also varies; it starts off slow and speeds up as it keeps blinking.



    And FYI, I installed Euro smilies today and nothing has changed with the turn signal situation. Thought this would be relevant information as the city lights are supposed to be hooked into the signal lights.
    • Member
    • Technical Service Advisor

    mooseheadm5

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    This is typically a problem with bad ground. If your light lights up dim, that is usually a dead giveaway. Often with E30s the plug that plugs into the back of the fixture is corroded as hell and rotting away. Look there, not just the bulb socket. Look for molested wires. Get an ohm meter and measure the resistance to ground on the bulb socket and plug. It should be almost 0 ohms (like 0.2-0.5 tops.)
    • Member

    az3579

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    Alright, I'll give it another shot tomorrow. Does removal of the turn signal assembly require removal of the bumper?
    • Member

    MGarrison

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    no - side marker lights pop out, one end has a spring on it. Rear taillight covers (that hold the bulbs) I think have a tab release, and the rear lenses unscrew/unbolt, as best I recall.
    • Member

    az3579

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    I'm talking about turn signal assemblies, the ones in the bumper, not the side marker lights.
    • Member

    az3579

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    Today I disconnected the connectors from the turn signal assemblies and checked. All the grounds have a clear path to ground, according to my multimeter. What else could it possibly be?????? :confused:
    • Member

    az3579

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    Yesterday, I took it a bit further.

    I took apart the steering column covers and tried out different turn signal stalks. I was 99% sure it wasn't the stalk but decided to give it a try anyway.

    I was correct in thinking it wasn't the turn signal stalk. I have 4 stalks available: the one that's installed now (for the 13-button OBC) and three standard stalks. All of them perform the same.

    I tried different relays. I had three other relays to try, and all of them caused the left turn signal to blink very fast (as though a bulb was out). I put back the relay I had in there, which is the only one that causes the left signal to blink slower than full speed. It still blinks at a speed between full speed (as though bulb is out) and normal. It also varies in speed occasionally, so it will start out slow and speed up, and slow down a little bit again.



    I checked the ground point on the steering column (at the signal stalk, ground wires, on the bottom of the steering column "down the line", and slightly above the column where the cluster of brown wires are screwed into that point. They ALL check out.



    WTF??????

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