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Blowing ECMI Fuse

7K views 5 replies 3 participants last post by  astro355 
#1 ·
So last night I was out driving around when I stoped to get a drink at a conveniance store. I left my 2000 safari running with the family. Got back in and backed out put it in drive and I made it about 4 foot before it died. It will turn over but no start. I can hear the fuel pump start up with key on. I checked all the fuses and found one bad one in the engine compartment. The ECMI fuse was blown. I put a second one in turn the ignition and it kinda starts just before it blows that fuse as well. The only thing that I can think of is that I had gently pressure washed the engine compartment earlier in the morning but I've done this many times before. But I put about 75 miles on it after the wash before this problem started. Any help would be appreciated.
 
#2 ·
Went back to the van this morning. About 20 hours after it left me stranded and replace the 20amp fuse under the hood for the ecm1 spot for like the 9th time and this time it didn't pop. Drove it home 27 miles no problem. Couple hours later went to run a few errands with no issue. Even later went back out and made it about a mile and while entering the freeway it popped the fuse again leaving me on the side of the highway. I just got home via a tow truck and now an hour later still continues to blow that fuse? The only thing on that cuirut is the crank position sensor, coil, coil control unit, and the computer.
 
#3 ·
There was a post somewhere on here about a crankshaft position sensor that kept popping the ecm1 fuse. I can't remember the fix for it or find the thread. Perhaps someone will chime in.
 
#4 ·
Finally figured out the problem. After testing the coil and coil module they both seemed fine and the wiring didn't seem to act up I turned my attention back to the third item which was the crank position sensor. The sensor tested fine and the harness seemed fine. But while running if I twisted the crank position sensor wiring it would stumble a little. After the third stumble it finally died blowing the ECMI fuse again. When I peeled back the wire loom and electrical tape to my surprise was that the first inch of the harness was completly missing it insulation on all three wires. The insulation was very dry and brittle for another inch but was still somewhat still insulating. Where the bend in the harness is where it is clipped to the oil pan again in that area was dry and brittle insulation. After checking all the way into the main harness and repairing the two areas I have now been back on the road for a week problem free.
 
#5 ·
great diagnosing skills you got there. any time there is a fuse that keeps blowing you should always look for a short which is usually exposed wiring.
 
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