My new front heater blower & resistor works & then don't.
First it squeaked & quit working. The next morning on my way to it turns on
full blast. The fan setting made no difference. Turned SUV off & it was sill
blowing full blast. Disconnected battery. After work I put in new blower motor
& still on full blast. Then replaced the resistor & it worked for 2 days.
Checked fuses & wire connections still nothing. I drove down the road a mile
& it starts working normal. The next evening quit again. So now I replaced
the HVAC & reset the system, but blower motor still will not adjust speed.
The rear heater works great.