Q: Heater blower stuck on high and will not turn off unless igniton is off

asked by on December 11, 2016

The heater blower is stuck on in the high position on my 2005 jeep grand cherokee and will not turn off unless the igniton is turned off or the fuse is removed. I had it checked out and was told i needed a new blower motor resistor as well as a new blower motor. Both were replaced, did the work ourselves and it did not fix the problem. Had it checked again, and was told that it was probably the temperature control switch. I ordered one and replaced the unit and blower is still stuck on high and can not be turned off. The resistor was replaced once before in October 2015 as well when this happened before but it did not solve the problem this time.
My car has an automatic transmission.

Blower Motor Relay Replacement $103.05 - $265.58 Get a Quote

This suggests that the relay may be supplying power to the blower motor regardless of turning the switch off. The blower motor relay supplies power to this motor when you turn the switch to "on" that can sometimes fail. When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blow motor to work intermittently. I would suggest having an expert from YourMechanic come to your location to diagnose your vehicle’s blower motor system.

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