Today a strange clicking noise started under the dash. I've sectioned it to a heater problem as it stops clicking when I turn the heat off. The clicking continues even when the truck is shut off
Most probably cause is the electrical actuator which moves the door directing hot and cold settings. Could also be a vacuum problem particular to the ac system. At any rate check the internet for a repair solution which is easy. Normally the dash has to come out to access the offending part.
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