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Using Headlight as a Short Finder
Posted to Technical Discussion Forum on 8/24/2010 63 Replies


Had some fun with this vehicle, I know this little trick has been covered before.

First job Monday morning, "we saved an intermittent short for you". (I was late, and nobody else wanted it :) Complaint says "every 2 weeks the ECM10 fuse blows and truck stalls. Gas station couldn't find problem. Tow In". So I walk out to the truck with a testlight and 10 amp fuse, found the ECM fuse (#15 position) missing completely, install my fuse, check all other ECM/Ign fuses and go to pull the truck in. As soon as I put the truck in gear, it stalls. Yep, blown ECM fuse. So now I get my headlight and put it in place of the fuse, truck starts and runs, filaments glowing very dimly. As I put it in gear and begin to move, I see this:

[Using Headlight as Short Finder]

What's next? Is there a better/quicker way to find this short?

Robert from Florida

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car Vehicle Data

2002 GMC Yukon SLT 5.3L

Engine5.3 L
Trans4-speed Automatic (Electronic)