I have a 1989 Pontiac Bonneville SSE and it does this weird thing where it repeatedly clicks near the climate controls intermittently. I took everything out and it's does it with the unit removed aswell. It also causes headlights to switch on and off extremely quickly. Seems to be a weird relay switching issue. It was initially triggered by pressing the off button on the climate control unit. I was hoping battery terminals, but after cleaning and reinstalling the issue will still happen. Where should I start digging, I was hoping it was maybe just a issue with the hvac unit, but I'm not so sure as the headlights and pretty much everything electrical seems to cycle on and off extremely fast(doesn't cause car to die). I just purchased the car and it had no issues with this until the climate off button was pressed.

It's tough to say for sure. I would pick up a factory service manual off ebay (there are a few available) and start tracing power and grounds for the wonky components.

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95 SLE... a keeper. 241k miles. Low and Slow.
97 BMW 528i
98 Infiniti vq35'd i30: 13.3@104mph, 30MPG Hwy (RIP)
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