Parking Lights Will Not Turn Off '92 deVille

[jbjconsulting]

Parking lights will not turn off on my 1992 Sedan de Ville.

I disconnected the push-pull light switch and the Twilight Sentinel switch and they are still on.

This is the front parking lights, all side marker lights and tail lights. When I pull the fuse the chime sounds. When I disconnect the push-pull headlight switch, the chime sounds. Brake lights and turn signals function normally.

The headlights will come on and go off with the push-pull switch and the Twilight Sentinel works, but only turns off the headlights.

Any help would be appreciated

[AMENCADDY]

Just noticed this thread and was looking at wiring in my same year FSM. There is another path for the current to get to those lights - thru the theft deterrent module. U can check by unplugging the module (4 wire plug) which is located left of steering column support, behind and above the IP fuse box. The turn signal flasher is there too as well as the plug for the TD relay.

[jbjconsulting]

Thanks for the quick reply. I just arrived home from a trip. I found a four-wire plug. It was just a plug from wire to wire. It was difficult to see where the wires were going so I'm not sure if I had the correct four wires.

When I unplugged it, the parking lights stayed on, but the chime started going off just like it does when I pull the fuse for the parking lights.

Any other suggestions?

[AMENCADDY]

ok, correction time. whatever u unplugged was not the theft deterrent. GM bad. I was looking at the component location sketch which was inaccurate showing a 4 wire connector. WRONG! (why does GM do that? IDK)

The actual connector is a long black 13 hole connector which plugs into the TD module circuit board. To get at it the fuse block has to be lowered. and since it is an awkward access you might even have to unscrew it from the bracket. I think the connector has a hook thingy on top, that would lift slightly with a screwdriver blade so you can unplug it from the control module. Since it is HOT at all times it is best to disable the SIR system ( me I would also disconnect the battery ) On the same bracket is the TD relay which has a shorter black 6 hole connector. Controller wire colors are one end will be black (GND) the other end will be orange (hot 12V).

Couple questions:
1) does your TD alarm system work normally.
with horns and lights flashing when tripped?

2) do your horns work from the steering column independent of the TD system?

3) which fuse is it that you remove to get the lights to go out?

4) the chime. does it go off continuously or just a one or two beep then stop?

5) have you checked for any OBD codes that might help diagnose this?

6) do you have skill to check the circuits with a VOM?

I'm baffled because you haven't mentioned your horns being on with the lights and the chime thing is weird. there are numerous fuses involved with the lighting system and a diode that separates the TD controller from the chime module circuitry. If the diode is shorted or open, guess what? bad news. and it's location is "taped to the main body harness." that will be fun to locate.
Hope this info may be of help.

[jbjconsulting]

I found the TD module and unplugged it. The parking lights still stay on. I have answered your questions below. Thanks again for all your time.

Couple questions:
1) does your TD alarm system work normally.
with horns and lights flashing when tripped?
>>Yes. If I lock the doors with the window open and pull up the lock the TD system activites. Unlocking the drivers door with the key shuts it off.

2) do your horns work from the steering column independent of the TD system?
>>Yes. The horn functions both when the TD is activated and from the column.

3) which fuse is it that you remove to get the lights to go out?
>>If I remove fuse 14 (park lamps) the parking lights go out, but the chime goes off more than once per second like it does if you leave the headlights on and turn the key off. Then I remove the Chime, Radio, Pwr antenna fuse to stop the chime so the I don't have to disconnect the battery every time I'm not using the car.

4) the chime. does it go off continuously or just a one or two beep then stop?
>>see #3

5) have you checked for any OBD codes that might help diagnose this?
>>Don't have the gear or know-how to do this. May have to take it to the shop.

6) do you have skill to check the circuits with a VOM?
>>Kinda. I have a good meter and can use it if I know what to check, but this is a little over my head.

[AMENCADDY]

Originally Posted by jbjconsulting

5) have you checked for any OBD codes that might help diagnose this?
>>Don't have the gear or know-how to do this. May have to take it to the shop.

6) do you have skill to check the circuits with a VOM?
>>Kinda. I have a good meter and can use it if I know what to check, but this is a little over my head.

oK, thank-you for your responses and I will look again at the schematics for you knowing all this.
if you look at the top of the forum page there is a "sticky" with instructions on how to get the OBD codes. you don't need any special gear and it is super easy. the codes display on your FDC after u enter the Diagnostic mode thru your Climate control panel. Save the bucks a shop will cost u and DIY. Just post the codes if any and it may help find the obvious short in your system.

With the VOM you could probly find the short that is keeping your light on. I can tell you where to check for the voltages for FREE. a shop will charge you the big bucks. Your choice. Let me know. I'll post later any more ideas I come up with.

[jbjconsulting]

Sorry, I don't know what a "sticky" is. I've spent a couple of minutes staring at the top of the forum page and don't see anything that leads me to OBD codes.

Thanks for all your help.

[AMENCADDY]

sticky = thread with commonly needed info. the moderator "sticks" it at the top of the thread list so it is easy to access by everyone instead of disappearing with the other dated threads.

anyway here is the link I was refering to from the Deville FWD forum.. Try! It might help pinpoint the cause of this problem.

http://www.cadillacforums.com/forums...ll-codes.htmlm (How To Pull Codes).

[jbjconsulting]

Fixed!!! After several attempts (thanks for all the help AMENCADDY), we figured out what the issue was. It was the Twilight Sentinel module not the switch. The module is a white plastic box about 3" square. My repair shop found it so I'm not exactly sure where it's located. My guess is up under the steering column. Anyway, you can just unplug the module and the headlights function manually without issue. Hope this helps someone else.

[AMENCADDY]

Thanks for letting us know. Electrical things can be so-o-o ... . lol