Well, I just can't seem to get to the bottom of this.......
My aux park fbh was working but not heating up interior, just defrosting the bottom 6 inches of screen. I chaged the faulty water pump with an alternative similar and either through screen manual switch or timer I can hear the unit fire up and the water pipes get hot, but the car blower only runs for about a minute and the interior does not get warm.
Is it a sensor prob? How warm should inside get? Unit works when I start car as I can see fumes from exhaust. (Tdv8 2007).