Valet fuse circuit question
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Melting Slicks
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From: Bradenton Florida
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Valet fuse circuit question
On the way to FunFest this past weekend my 94 blew the valet fuse which powers the transmission solenoid packs and also feeds the alternator. I have dissected the wiring, took all of the wiring and solenoids out of the transmission, have that complete circuit disconnected, removed the PCM and battery from the car and still had a dead short going from the fused side to ground. This morning I took out the alternator and as I disconnected the regulator plug from the alternator my circuit finally went open. OK shorted alternator I thought. Just had it tested at 2 different shops and both tests say the alternator is good. The only things on this circuit are the feed for the field on the alternator and the feed for the trans solenoids. With everything out the circuit is clean. Even with the fuse blown the alternator was still working with no field being fed. So even though it tests OK, I think the regulator has to be shorted internally. There is no other place for this circuit to pull ground from unless a wire has chaffed. Which I just confirmed is not the case with my last test. Has anyone ever seen this before? Also with the feed being open how is it getting a field voltage?
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Guess I'm a bit confused? valet Fuse and transmission solenoid packs? This is a 94 auto?
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Melting Slicks
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Melting Slicks
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I finally found the culprit! The plug for the alternator was shorting out which blew the fuse and then took out the trans. At least the wiring was intact. Waiting on the new solenoids I ordered, as the car has 171,000 miles and as long as it's open I will change out the electrical parts in the trans. It will also get a new filter and flush and a new speed sensor which will fix the drip I was having.
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Very interesting, glad you got it worked out. 
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I finally found the culprit! The plug for the alternator was shorting out which blew the fuse and then took out the trans. At least the wiring was intact. Waiting on the new solenoids I ordered, as the car has 171,000 miles and as long as it's open I will change out the electrical parts in the trans. It will also get a new filter and flush and a new speed sensor which will fix the drip I was having.
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Melting Slicks
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Melting Slicks
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I finally got the car to do the hot no start in my garage a few weeks ago. I was able to test for fuel / spark etc. I had plenty of fuel, but no spark. I took a bag of ice and put it on the PCM waited a minute and the car fired. I surmised the the PCM was getting hot and opening up. I replaced the PCM. Everything was good until the trip down to FunFest again. After stopping for gas, she went to start the car and it did the long start again. This time she set a code which I pulled once we got to FunFest and had set up. A bunch of codes for the transmission, and a code 36 which is a data stream code. I figured out the Transmission codes were from the blown fuse which was a separate issue. The Code 36 however is a Opti Spark code. I replaced the Opti when we got the car and it only has about 5,000 miles on it. But as I keep researching the telltale signs of a dying Opti are the Hard, long start, no spark. I am going to upgrade to a Petris Vented Opti now that EVERYTHING else has been replaced. Hopefully this will cure the hard start on hot condition and Emily can rely on the car again.
Drifting
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Kevin, I am certainly no expert with the LT1s but my previous offer to help is always open.
I believe the code 36 is almost always the Opti itself but I have read to check the connector as well.
Good luck and keep us posted.
I believe the code 36 is almost always the Opti itself but I have read to check the connector as well.
Good luck and keep us posted.
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Melting Slicks
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From: Bradenton Florida
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St. Jude Donor '12-'13-'14-'15-'16-'17
I got her up and running. The connector at the alternator shorted out. Replaced that and put all new solenoids and wiring in the transmission just because of the miles on the car. Runs great, shifts smooth, charges.
I am ordering a Petris vented Opti which is supposed to be the cure for the dreaded Opti failure. All good again!
I am ordering a Petris vented Opti which is supposed to be the cure for the dreaded Opti failure. All good again!