m38inmaine
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- Maine USA
My recent M1008 purchase from GL was listed as no start. Seemed to be the famous starter relay as it was removed and in the seat when I got the truck. I replaced the relay and it started so I thought the problem was solved. After a recent fuel pump/fuel filter change while I was cranking to bleed the filter it stopped cranking. Checked the relay plug and no 12v power coming in from the ignition. Jumped the incoming 24v and the starter wire and it cranked. Next to the ignition switch, took it out and it bench tests fine. Jumped the 12v from the ing switch plug to the yellow wire and it quickly wanted to melt!, short to ground somewhere. Followed the dreaded purple wire circuit out to the engine compartment and in the center of the loom it exits into a loop through a diode and back into the loom. I found one side of this loop half rubbed through and burnt! It has been rubbing on top of the vacuum pump for some time and causing a short whenever it felt like it. Whats interesting though is after all my attempts at cranking and the circuit shorting out to ground the fuse never blew. These CUCV wiring problems can be tough, but with the trusty multimeter and a little patience can be tracked down.