I have 31 years' experience as a technician, to include 22 years active Army. I'm currently retired and trying to help a friend. He has replaced the starter, battery and all 3 relays. I swapped the relays with other know goods, with no change. I bypassed the brake sw and got no change. I did not bypass the neutral safety because the car doesn't start in N or P and figured it was good. I'm getting 12.4v on both sides of fuses 2.5 and 5, as well as spot #2 on both cut relays. I am getting 12.4v on the opposite side of #1 cut relay, while pressing start sw. I'm getting 2.5 constant volts, regardless of pressing start button or not, on #2 cut relay with no change while pressing. I get 12.4 volts on both sides of the inhibitor relay, under the dash. My thoughts now is that it may be a failed transistor inside of the PCM itself. It's one of the most complicated starting systems I've ever worked on and even though I'm really good at troubleshooting electrical issues, this one has me baffled. Thoughts?
Monday, September 9th, 2024 AT 4:05 PM