HELP! GMC Sierra Ignition/Fuse Issue

[hanson]

1999 GMC Sierra Ext Cab 4x4 5.3l, about 203,000 miles on it.

OK... Drove home from work today, truck was running fine. Parked in the driveway, went in and changed clothes, grabbed my muskie stuff and away I went. Wrong!

Turned the key and nothing. Nothing! No starter turning over, nothing.

Underneath the hood, in the fusebox, I have a 40amp fuse labeled 'Ignition' that was blown. Picked a new one up at the auto store, popped it in, turned the key and blew the fuse again.

What the heck is causing that fuse to blow?

One minute, truck is running and starting absolutely fine. Next minute, its blowing this fuse. Grrrr....

Any ideas?? Now I gotta figure out how to get to work tomorrow.

[herdog]

Hanson:

Don't know if you have this figured out yet but my first guess would be a shorted out starter. Did it turn over at all after you replaced the fuse?

[herdog]

Second guess would be a shorted alternator. If your inclined (sacrifice another fuse?) you could losen the belt and rotate the alternator half a turn & try again.

[hanson]

Hanson:

Don't know if you have this figured out yet but my first guess would be a shorted out starter. Did it turn over at all after you replaced the fuse?

Nope. Never heard it crank at all.

[Scott K]

Chris, it looks as though the main draws of this circuit are the starter relay, and a feed to the ignition switch that are all fused seperatly. I would remove the starter relay and see if the fuse will still blow, if it doesn't you know it is in the starter circuit. More then likely, a bad starter.

If you want a wire diagram let me know, I can email one over to you.

[hanson]

I started with the starter, pulled it out and brought it over to my neighborhood O'Reilly. They ran a test on it and it passed twice. Starter and starter solenoid aren't the issue.

Now I got to put that ******* back in there. Engineers I tell ya.

This problem is really ticking me off.

[hanson]

Well... she's running now. Nother mystery of the universe.

Best I can figure is I have a dead spot on my starter now that caused that short. Like I mentioned, brought it into O'Reilly and they ran a test on it, worked fine. Put it back into the truck, popped a new fuse in the panel, turned the key and she fired up. I've since restarted the truck about a dozen times with no issue. Go figure.

Only other thing I can think of is I disconnected the battery before I removed the starter. Not sure if that reset something or what but I'm currently in business.

Guess if it happens again, I'll probably just put a new starter in it.

[LMITOUT]

Uggh. That's one of those pucker problems where you pucker every time you hit the key and hope it fires when you're away from home because you know in the back of your mind that you really never found the problem.

Better carry a few extra fuses and a dead-blow hammer to give the starter a whack when it happens again.

[jeffreyd]

could have been the starter solenoid pull back hung just a tad, enough to put a draw on the circuit. Is the heat shield in place on the starter? also could be a wire in the steering column that got pinched and moving the wheel/shifter might have moved it a bit. If you let the truck sit overnight, before you try and start it, open hood and feel the altenator to see if it is warm. That would also indicate a leak however your not loosing power just popping the fuse. I hate gremlins. They stink