Having problems with your Cars & Trucks ?
I have a 99 tahoe and my heater is always on. I can not turn it off the A/C doesnt turn on. I had recently change the headunit.
Wires to A/C commutter not correctly connected or A/C commuter broken. Replace it with the old one, on the old headunit
Repair Help & Product Troubleshooting for Cars & Trucks
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