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The AC button on the dash of my 1987 truck quit working the other day. Pushing it does not send 12v to the AC compressor. Is there a relay/fuse that is associated with the button? If so, where is it located? Thanks
Sorry, I read every thread but no that didn't help. I had already checked every fuse in the truck and found them all good. Yes, I found the AC and Heater fuses that are hidden behind the glove compartment.
The switch on the panel provides power to the A/C Amplifier (located above the evaporator box). The Amplifier then decides on whether to provide power to the compressor clutch. It won't provide power, for instance, if the refrigerant pressure is too low. I'd start with the gauges.
The light on the switch just indicates the switch position. If you don't get the light, you can have a burned-out LED (unlikely) or an open somewhere in the battery line (e.g., blown fuse).
The switch on the panel provides power to the A/C Amplifier (located above the evaporator box). The Amplifier then decides on whether to provide power to the compressor clutch. It won't provide power, for instance, if the refrigerant pressure is too low. I'd start with the gauges.
The light on the switch just indicates the switch position. If you don't get the light, you can have a burned-out LED (unlikely) or an open somewhere in the battery line (e.g., blown fuse).
Thank you. The button light does light when pressed. So, it must be that the amplifier has decided not to send 12v to the compressor clutch. I've already hooked up a temporary jumper from the battery to the compressor and my system has been cooling just fine all summer (Tampa, Fl.). I'll take a look it that amplifier and its wiring, maybe I'll see something out of whack. Thanks again.
Aug 7, 2025 | 12:22 PM
