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GT350 Alternator and Harness replacement

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Bay Area
I know someone has been through this. I cant find it. What is the PN for the harness that gets heated up and fries the alternator on the GT350? Please tell me its the cheap one.

Screenshot 2023-08-31 at 7.58.55 PM.png
Can you guys share some additional context? I'm wondering if that harness is the reason I've already replaced one alternator (at 7k miles) and my instrument panel still occasionally loses power. I had the "charging system fault" message on the track before I replaced the alternator. The error hasn't returned, but the instrument panel completely loses power at random and not at all reproducible moments.
Exp. Type
Exp. Level
Under 3 Years
Nashville TN
You sure you aren't having the issue where the voltage regulator pigtail has internal breakage and behavior is voltage all over the place? That's just WPT-118, costs about $17.
I was watching my voltage on the digital display during a test drive on Saturday. My instrument panel voltage moved between 12 and 15, depending on RPMs. Having never watched it before, I'm not sure if that is normal or not. The instrument panel never lost power during that drive.
Bay Area
I wish I could help you out also. I know my harness was getting heated up and it was ontghe lst of things to do. Obviously, it got worn out before I could save the alternator. I suggest you check the harness next time your under the car and that area. If I remember when it gets replaced Ill get some pics.
Hey D.J. Todd I'm having the same problem with my 2017 GT350R. Three dealerships , three alternators , and two auto electrical shops later. No one has been able to fix the problem yet. I'm getting pissed off because these guys take the money fix or not.
Sorry to bump this thread, its not that old.

I am having issues with my GT350 where it has sudden voltage spikes and has killed 2 cam sensors and a wideband. I bought a replacement engine harness to start and have replaced the sensors.. is there more documentation around this "voltage regulator pigtail has internal breakage"? @ChipG

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