Hi, I need help tracking down a short on fuse #8 radio / headlight switch. it is the black and pink hot in run wire. I have the fuse pulled, the radio and headlight switch connectors disconnected, the ignition switch and the plug to the GEM disconnected. I am sure the short is somewhere in the wiring harness unless there is something I am missing. Help for where to look would be appreciated. I can't imagine a wire has gone bad in the harness by itself, are there other connections / splices I am unaware of!
Thanks!

 

If you have the GEM module, Radio, and light switch disconnected and you still have a short to ground on that wire, it's either the fuse box or the harness.

There's nothing else on that circuit according to the EVTM.

 

I think its the GEM, I removed it and the short disappeared, plugged it back in and the short was back. Unless it it in the fuse box connection. Any Ideas how to test the GEM for a short?
Thanks!

 

You just did...

Or, you can pull out the GEM and test the input pins with an ohmmeter.

 

I would swap it out. Here's some places in California with a 99 truck. I went to Car-Part.com--Used Auto Parts Market and looked up "computer not engine" and you can see all the many choices their are and how many numbers there are for the different modules. I believe they are calling the GEM module the "multi-function module". But no junkyards came up, it's probably too much of a hassle for them to list all the different modules they have. So I looked up a front fender instead, and these are the ones that came up with that in California that were a 99. I am not sure if any of the other years will fit, and you will probably have to go to the yards, pull the module, and verify the numbers yourself. It's a little bit of work, but you can probably get it cheap that way. Just make sure it doesn't look like it has any water damage from a leaky windshield, which is a common problem in these models.

1999
Fender
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Fender
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Fender
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1999
Fender
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Thanks for the replies, especially Franklin2 for the research "above and beyond". I have the GEM pulled but do not know what normal readings would be with my VOM or which pin is which. I am thinking about getting a new one on Monday.