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Electrical Gremlin

12-05-2010, 09:50 PM
Ok I know there are a few electrical guys here so I am gonna quote myself from a thread I made on another forum.

Some of these are responses to questions being asked.

I was sitting here watching some football and my brother informed my headlights were on. I was a little confused because I know there weren't on when I got back from picking up pizza earlier, but sure enough they were on.

I opened the driver's door and went to turn the switch back and to my confusion it was already back. I turned it forward and back again and the headlights remained on. I flipped it back and forth several times and nothing changed.

I popped the hood and pulled the main light fusible link and all light remained on. I pulled the headlight relay and they finally went off. I swapped the relay with the fog relay and the lights worked with the switch.

But there's a catch. When the headlights are off, the MFI relay buzzes like crazy.

I messed with it some more and made the relay quit buzzing, but anytime I turned the headlights back on, then off again, it buzzed again.

I just unhooked the battery for tonight because it was 11 oclock and I was out there with a flashlight and in shorts.

Anyone have any clues before I tear into it tomorrow? I dont know if its a relay issue, or maybe something with the headlight switch itself.

Any input ahead of time is appreciated.

I'm about to get dressed to go out and mess with it more now. I'll see what I can figure out and report back with any new findings if I still can't figure it out.

As for the questions.

No I dont have an alarm.
Battery is less than a year old and the lights were bright when they were on.
I didn't have my keys on me when I was messing with it last night.
Didn't get the tail relay pulled but will check it out.
No wire munching that I know of.

Ok I went out and pissed with the car. I realized that in the confusion of the dark and the cold last night that I didn't pull the headlight fusible link, so that explains why the lights remained on. Another thing I remembered is that only the headlights were remaining on. When I turned the switch back and forth the parking lights were going on and off.

I cleaned up the battery terminals because they had a little corrosion on them, cleaned up the posts, then hooked the battery back up and everything seems to be working like normal right now. I don't know if just the relay got stuck on its own or what. I'm going to keep an eye on the car today to make sure the lights dont come back on again. Hopefully it was just some weird hiccup the car had to get out.

The gremlin must be in from the cold again.

I decided to go out and make sure the car started ok and that the headlights worked as they should. I turned the headlight switch on and turned it back off only to have the headlights remain on, while the parking lights were off. As soon as I started the car the headlights turned off.

I kept getting this to repeat and then looked down to see the brake light ever so dimly lit when the car was off. I put the ebrake down and the dim light went out.

Is this sounding like an ETACS issue? I don't even know where else to begin.

EDIT: BTW I pulled the headlight fuse under the dash while the headlights were on, and they remained on.

Yeah, they shut off when I pulled the headlight relay last night. I then swapped it with the fog relay.

I think something is happening making the headlight relay stick. I don't know what would cause that though.

The headlight shutoff works as soon as the door is opened and the keyswitch is off. There is no "delay" so to speak.

12-06-2010, 09:27 AM
I'm no expert but I would replace the relay and see how that does. I'd love to hear the solution to this too.

12-06-2010, 11:05 AM
It sounds like either the ETACS or Automatic Shutoff Unit. I have uploaded the pertinent repair portions to help diagnose the problem. Based on your description of the problem and the troubleshooting section of the attached pdf's, I am leaning towards the ETACS.

I could not upload a complete pdf with all of the parts because it was greater than the limit allowed for this site so I separated them.

HL_Des_Op is the description and operation of the automatic shutoff system
HL_TS is the troubleshooting section
HL_Testing-ASU is the testing of the automatic shutoff unit
HL_Testing-InputSig is the testing at the diagnostic connector
HL_R-I is the for removal and installation of ASU
HL_diagram is the wiring diagram of the headlight system

12-06-2010, 07:54 PM
Well thanks to help on another forum I think I have it fixed.

I was pointed toward the auto shut off relay. After being pointed toward that I am kind of kicking myself in the ass because I should have thought of it myself. I unplugged the relay without testing it at first, just to kill the lights entirely.

I went back out and was going to plug it back in so I could test it and realized something odd. It was wet, very wet. Oddly enough a guy I know posted that possibly the headlight relay had gotten wet and was freezing due to the cold temps causing a short in the relay.

I opened the relay up and it was very wet inside. It all makes perfect sense now.

I think what happened is a few weeks ago we had some really bad rain storms and my sunroof was leaking pretty bad. I already have the speaker panels off and the relay was laying loose because of me previously testing it. I think some of the water and moisture got to the relay, then the recent cold temps caused my issues.

I appreciate the attempts at help from both of you. :)

12-06-2010, 11:13 PM
Good hell, water...

I'm glad it was something simple. :biggrin:

12-07-2010, 11:58 AM
glad you found the culprit

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