Going by your description I take it is your heater fan at fault. A common problem is a blocked pollen filter putting strain on a fan and eventually burning out the motor. I would start by checking the filter and locating the fan,maybe disconnect the terminals to the fan and try a direct 12v feed onto it,if it works the you may have other problems,if not then try a scrappy for a new unit.
cdc
January 2015
howtomendit.com for free repair help, information and advice.
