2004 Honda Accord EX Sedan

heating

#1

Nothing will blow out from vents, with heat or AC. I checked the fuse under the hood and that had continuity, I checked the 7.5 fuse under the dash and that was fine. I also replaced the blower motor resistor and the blower motor with brand new ones. Also used a test light to make sure power was getting to the resistor and motor and that is all good. Does anyone have any other suggestions on what to check?


#2

Could the fan speed switch on the dash be bad? Check the ignition switch, perhaps is not sending power to the fan circuit?


#3

Check the blower motor power transistor.

Tester


#4
I also replaced the blower motor resistor and the blower motor with brand new ones. Also used a test light to make sure power was getting to the resistor and motor and that is all good.

So, you see 12V at the blower motor, but the blower motor doesn’t run?


#5

The reason the blower doesn’t run is even tho 12V power is supplied to it is, if the blower motor transistor has failed, the blower motor is no longer grounded.

Tester


#6

Sure there’s 12V at the blower motor. I bet there’s 12V at the blower any time the key is on. The switching and resistor and associated wiring is all on the ground side.