When the problem occurs, if your saying the starter motor won't crank, then check voltage at the starter circuit.
When parking on an incline. Engine running, foot on the brake, set the parking brake, then shift into park. Let the parking brake hold the weight instead of tranny. Don't know if that will help?
I have no idea what the heater switch has to do with anything?
Maybe a problem with feed from ignition switch?
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Saturday, December 29th, 2012 AT 5:44 PM