Just talked to my buddy (owner). A month ago when I first reported this issue, I also told him to keep driving the car but without the A/C. He has been doing this and hasn't run into any issues. Hasn't had to jump the car, and the flickering in the dash and headlights is all but gone. Definitely sounds like an undercharging condition to me, as if the system can't overcome the electrical load that the A/C puts on the system.

He is going to leave the car with me in a couple weeks when he goes on vacation. I will start by looking at the battery cables (pos & neg), the grounding strap(s), and the harness going to the alternator. Interestingly, he left the car at the dealer (Ewing in Plano) and paid them $200 for a diagnostic. They did not find any charging issues but told him his gauge cluster was bad along with a few other things such as the rearview mirror needing replacement. They did not elaborate on the cluster. The cluster has been "bad" for 4 years but he never had it replaced. He never had these electrical issues until the last 6 months or so - is there ANY way possible that the cluster could be causing this? Seems to me that if the cluster was the problem then it would occur both with the A/C on and off.

I appreciate the suggestions given previously - any others?

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