Nissan Repair Questions? Ask a Mechanic for Answers ASAP
That sounds odd that the alternator will pass a load test but you can't load test the system with the AC on. Can you test for voltage draw with the AC on? You will need an induction clamp and a multi-meter.
An induction clamp will measure the amperage flow from the alternator/battery. This will tell you if there is some sort of voltage stealing short in the AC or something that activates along with the AC, like the AC clutch or cooling fans.
Has the battery been tested on a load tester?
So this only happens when you turn on the AC? What if you turn on the heat full blast and the high-beams? That should be more of an electrical load than the AC.
That's where I was leaning- makes sense. It throws you off when the testers says "ok" but it just doesn't work right.
Please let me know if you need help in the future.
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