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Old 09-20-2004, 12:12 PM   #21
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Quote:
Originally Posted by willwren
I think it'* time to shoot out the wires from the switch to each lamp assembly. The Chilton'* schematics have wire colors listed for the exterior lights circuit. I think doing anything else but this would be a waste of time at this point.
Well, the wires to the individual lights are not distributed from the headlight switch; they're distributed from the ALM. As I indicated, the headlight switch turns on the brown wire, and that'* all. When I was doing my remote starter installation, a single connection to the brown wire to inject a 12-volt pulse (the remote starter blinks the lights to acknowledge receiving your signal) was sufficient to light up all the exterior parking lights, as well as the dash gauge backlighting.

Incidentally, the circuit breaker built into the headlight switch protects only the headlights, nothing else. All other lamps are protected by fuses.

I know jachin sez that he'* not measuring any voltage at the brown wire, but if the front parking lamps are still working, then the brown wire at the headlight switch must still be functional. (If it isn't, then I am going to get a very big headache and go lie down for a while...)
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Old 09-23-2004, 02:07 PM   #22
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OK guys, i replaced the headlight switch, and nothing has changed at all. Now where do i go?
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Old 09-23-2004, 03:11 PM   #23
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I wouldn't have replaced that switch. You should start with shooting the wires from the switch to the socket. Don't do anything else until you've done that. Your Chilton'* should be accurate on the wire color for that.
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Old 09-23-2004, 06:55 PM   #24
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You're supposed to test before you replace things....
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Old 09-24-2004, 11:58 AM   #25
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Quote:
Originally Posted by jachin
OK guys, i replaced the headlight switch, and nothing has changed at all.
That'* correct; nothing would have changed.

As I said 10 days ago:

Quote:
[...] your headlight switch has only one output to all the exterior running lights, and that'* the solid-brown wire, so if _any_ running lights on your car are lighting up properly, your taillight problem is not due to a bad headlight switch. (By "running lights" I mean your front parking lights, taillights, license plate and side-marker lights front and rear.)
Quote:
Now where do i go?
As I said 7 days ago:

Quote:
[...] I would suggest you start at the back of the car, verify that the brown wiring is actually dead back there, then follow it forward to see where the break is.

In particular, look for damaged or broken connections in the wiring harness in and around the trunk area. Wiring that'* exposed to the elements or junk sliding around in the trunk is a lot more likely to go bad than wiring that'* immobilized and protected inside the car and up under the dash.
Please do that, and let us know what you find out.
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Old 09-24-2004, 01:10 PM   #26
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Quote:
In particular, look for damaged or broken connections in the wiring harness in and around the trunk area. Wiring that'* exposed to the elements or junk sliding around in the trunk is a lot more likely to go bad than wiring that'* immobilized and protected inside the car and up under the dash.
Good advice from page 1.

Quote:
The only thing i can think of is when i pulled the trunk lid off. i didnt disconnect everything, i just set it on saw horses beside the car, a wire may have been pulled out. But right now the switch seems like the most logical cause, because i tested the brown wire directly at the switch with the lights on and it was registering no power. I also tested the socket for the bulb and it didnt have power.
You better look more carefully.

Quote:
I'm leaning towards the ground as well. Here'* some info from my diagrams:

Adaptive lamp module:
Pin E - tan/white - runs L & R tail lamps
Pin C - purple - runs L & R tail lamps
Pin D - pink - runs side markers and license plate lamps

G402 - LH rear of luggage compartment, behind wheelhouse.
Quote:
I think it'* time to shoot out the wires from the switch to each lamp assembly. The Chilton'* schematics have wire colors listed for the exterior lights circuit. I think doing anything else but this would be a waste of time at this point.
Quote:
Alright, thanx guys ill get to this on my next day off.
So what happened when you checked the wires?

Quote:
I know jachin sez that he'* not measuring any voltage at the brown wire, but if the front parking lamps are still working, then the brown wire at the headlight switch must still be functional. (If it isn't, then I am going to get a very big headache and go lie down for a while...)
Quote:
I wouldn't have replaced that switch. You should start with shooting the wires from the switch to the socket. Don't do anything else until you've done that. Your Chilton'* should be accurate on the wire color for that.
Jachin, not intentionally beating you up, but you skipped a few steps we asked you to take for YOUR benefit. You would have had this fixed by now. Please take these troubleshooting steps, and get back to us with the results. It'* really quite simple. If you follow this advice, you'll have it fixed the next time you post.
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Old 09-24-2004, 03:54 PM   #27
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I'm sorry; we've got at least a couple of errors to correct here.

First of all, I screwed up by saying that you need to check the brown wire in the trunk to see if it'* live. Since the car has a Driver Information Center and an Adaptive Lamp Monitor (ALM), there is no brown wire in the trunk.

This car doesn't power all the exterior bulbs on the same brown wire that comes out of the headlight switch. That brown wire only gets far as the ALM; at that point its power is divided out to several differently-colored circuits, including at least three that go to the back, so that the ALM can monitor the bulb groups individually to tell you whether, for example, you have a burned-out light in the front or in the back.

This brings us to boo-boo #2:

Quote:
Adaptive lamp module:
Pin E - tan/white - runs L & R tail lamps
Pin C - purple - runs L & R tail lamps
Pin D - pink - runs side markers and license plate lamps
Purple is for the left and right brake lamps, not taillamps. No biggie here; it sounds like you need to verify both the tan/white wires and the pink ones, since you said that both your taillamps and your rear side markers are out. (Thanks to randman1 for sending me that excerpt of the wiring diagram, so I didn't have to wait to get home to look at a manual.)

It'* important to start at the back of the car and follow the wiring forward, so that you're starting at the dead end of the circuit. Starting inside the dash will simply get you (more) confused, and the problem is less likely to be up at the head end anyway. The connections in the trunk are where the problem is most likely to be found.
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Old 09-24-2004, 04:07 PM   #28
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Quote:
Originally Posted by acg_ssei
Purple is for the left and right brake lamps, not taillamps
Actually, purple is for the tail lights. Orange is the wire color for the stop lights. This info on another diagram
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Old 09-24-2004, 04:45 PM   #29
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Quote:
Originally Posted by randman1
Quote:
Originally Posted by acg_ssei
Purple is for the left and right brake lamps, not taillamps
Actually, purple is for the tail lights. Orange is the wire color for the stop lights. This info on another diagram
Huh? I'm looking at the diagram you sent and it quite clearly indicates "TAN/WHT" for the taillamps and "PPL" for the stoplamps. There is one additional detail I didn't catch before, and that'* that the Pink wire to the license plate lamps changes to Brown after Connector 401.

Orange is normally unswitched accessory power, such as (in the back) for a trunk light or power antenna supply. Oh, wait a minute: you might see orange as an input to the brake lamp switch, but that'* up under the dash.
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Old 09-24-2004, 04:53 PM   #30
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Quote:
Originally Posted by acg_ssei
Huh? I'm looking at the diagram you sent and it quite clearly indicates "TAN/WHT" for the taillamps and "PPL" for the stoplamps. There is one additional detail I didn't catch before, and that'* that the Pink wire to the license plate lamps changes to Brown after Connector 401.
Okay, okay, I need more coffee. I think I follow this now: Purple is the feed to the taillamp filament of the brake lights; Tan/White is the feed to the taillamp-only wedge-base bulbs in the trunk lid. The _brake_ circuit of the brake lights is indeed another color not on the diagram I have.

Got it now...
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