Electrical Problems ... HELP Please!!!

[repstate]

Hey Guys,

I have a 2001 Excursion with a 7.3 Powerstroke in it and it has 167000 miles on it and it started to have some weird electrical problems.

Fuse 28 is blowing at different times and I can't figure it out. Sometimes it blows as soon as I turn on the key and other times it waits a little while and then blows. It blew this morning when I hit the right turn signal, and again later when I put it in drive. So, I don't know where to start.

It is a 15A fuse (per the book) and it controls the flashers, turn signals, vacuum pump for the 4X4 shift on the fly, instrument cluster trouble lights, and the overhead console.

I called Ford and they said to replace the vacuum pump because as the get old the start to draw too much current which will blow the fuse. I have since replaced the pump and the problem still exists.

My truck is stock with the exception of a Gear Vendors under/overdrive unit.

I am at my wit's end.
Please help.
Any ideas would be appreciated.

Thanks,

[ocrush]

Im not sure if these may be the issue, but I recently had to replace both in my 2000 EX 4X4 7.3 that has 137K. The transmission safety switch.(My truck radio would shut off when it was put into reverse) and the turn signal switch relay. directionals would go on but not blink. (this is located behind the lower dash panel that holds your wallet and stuff ashtray removal as well). Like I said not sure, but sounds similar. Good luck!

[goats]

I had a problem like this on my ranger and it was sooo randam how about you look at the wires for the overdrive switch on the collom where the wires come out of the shifter sometimes it makes a tight turn and the wires may rub and cause a exposed spot on the wire and could be grounding out

[powerhoghp]

Where is the OD/UD unit wired for power?