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Exterior light circuit schematic?

1K views 13 replies 3 participants last post by  Doward 
#1 ·
I posted about this in the Electronics section, but figure there's more eyes here.

tl;dr - My exterior light 15a fuse immediately blows when I flip the headlights on. I've removed all the bulbs all the way around, still blows - so I'm 99% certain it's a wire rubbed through somewhere.

Hoping someone has the diagram so I can start tracing the wiring... ?

Thanks!
 
#2 ·
Have you checked at the trailer plug for loose wires?
 
#3 ·
Key off, headlight switch off, no fuse in the #17 spot.

Ran a continuity test to ground - only the bottom left of the 7 pin and single 'exposed' of the 4 pin beeped at me. That leads me to believe no shorts to ground in the wiring between the fuse and the receptacle for the trailer wiring.
 
#4 ·
Possibly the wiring in the steering column that runs to the headlight "dimmer" switch? -- the transmission shifter mechanism and the wiring in the column can get together and cause all kinds of fun problems -- could disconnect the column harness and see if that locates the problem
 
#5 ·
I'll check out the wiring in the steering column, too.

Nobody has the schematic, though? It'd be extremely helpful to know where the fuse sits in the circuit, for instance, so I can test both sides of the fuse (and hopefully narrow down where my bad wire is!)
 
#6 ·
#7 ·
These might be better.
 

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#9 ·
Update on this!

Wiring book came in. What a freaking difference that made :D

Ruled out any issues pre-headlight switch. It's the brown wire. Disconnected *everything* external, checked for continuity between the brown and black wires on the mirrors - confirmed I have a short in the wiring.

Tone generator showed up today, but I was in the middle of rewiring my FIL's old trailer, so didn't get a chance to start tracing today.

Hopefully I'll be able to find out more this week, though!
 
#10 ·
Took the day off of work for some appointments, trying to do more diagnostics.

I've disconnected every single connector I've been able to locate - still have short to ground on the exterior lighting power wire (brown). Got my hands on a tone generator, and it turns out since I'm shorting to ground, trying to trace the wire in the dash is a lost cost - every ground (including the metal frame) is naturally causing the tone locator to light up!

I've basically resigned myself to having to take the entire dash out at this point. I DO have an '08 dash I was intending to swap - maybe I'll just start on that. At least after all the effort I'll have something a little more worthwhile than 'the exterior lights work again' :)
 
#11 ·
Possible short in the door hinge area?
 
#12 ·
So the tl;dr of this bit of fun - I did what you see in the first picture, finally was able to trace the wiring enough to tell where specifically in the circuit the issue was, only to find the culprit was the second picture.

The real interesting thing? The stupid thing still glowed - but since they are never bright to begin with, I didn't think anything further.

Oh well, at least the inside of my dash is much cleaner.

Dress rehearsal for the '08 dash swap I'm planning for my christmas vacation, I guess.
 

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#13 ·
what part was bad? bulb or socket?
connections were touching inside?
 
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