Odd electrical gremlin

[stangman92gt]

Hey guys:

I recently picked up an '89 LX 5.0 after being out of the Mustang scene for a few years. It's fairly rough but I got it cheap.

Anyway, I have a dead short on one of the lighting circuits.

It had fuse #4 blown already. I stuck in another fuse and it blew as soon as I inserted it.Not wanting to waste fuses, I started testing with my meter.

I removed the headlight switch and that killed the drain. So, I removed wires out of the headlight switch connector until I found the one that is shorted, and it's the R terminal.

According to the schematics I have available, that's the one that loops past the panel dimmer, chime relay and then to the LCD display relay for the stereo.

I began removing each of those components one by one and testing, and I still have the draw with everything in the circuit removed.When i put one terminal of my meter on 12v hot in the fusebox and the other on the R circuit, it draws battery voltage through and that doesn't seem right.

HOWEVER...that circuit keeps going somewhere past the LCD display relay, and my modest schematic doesn't indicate where. I need to find out so I can locate the grounded spot.

I HAD a factory shop manual somewhere, but I can't locate it, so if someone could tell me where the R circuit ends up after the LCD relay, I would appreciate it. This is the circuit that feeds 12v with the lights on to trigger the lights on chime and the dimmer for the stereo.

Alternately, if I'm mistaken about this and I have a problem somewhere else please feel free to let me know your thoughts.

Sorry for the long post!

 

[jrichker]

Pm me your email address and I will send you a complete Ford Factory 89 Mustang electrical diagram set. The zip file is 2.5 MB and is too big to fit through Stangnet's email gateway.
89 Mustang wiring diagrams zip package–

They are in a zip file format to reduce the size of the package. You’ll need WinZip or other Windows archive tool to extract them from the zip file. See MajorGeeks.com - Download Freeware and Shareware Computer Utilities. for a free download.

You will need the Adobe Acrobat viewer which is also a free download – Adobe - Adobe Reader download - All versions

 

[stangman92gt]

Thank you again for sending this, it was a lifesaver. I would highly recommend that anyone doing serious work, especially wiring, pick up the factory manual for the car, from FORD.

I will add that I got punked on this problem, haha. The problem turned out to be a headlight switch that was broken internally. I was getting power to certain terminals when I shouldn't have been. If you ever take one of those switches apart, it's a sliding piece riding on a ball bearing..pretty hokey.

New switch fixed 'er up.