heater

Nov 15, 2006 8 Replies

I got a ford f-150(1992) and well not the heater, but the fan itself will not turn on unless it is on high. I put it on low and medium and nothing happens, but when I put it on high it always turns on. I'm curious does anyone know what this could be? it is a manual tranny with a 6cyl 4.9L.



On Wed, 15 Nov 2006 03:21:17 -0800, mitsurugi3644 rearranged some electrons to form:

Blower motor resistor needs to be replaced.

The blower motor speeds are controlled by the resistor pak which is controlling the ground to the motor. Having only High speed means the motor has a direct connection to ground. The lower speeds use higher resistance because of the different values in the resistor pak. The pak is located in the blower-motor housing on the passenger side in the engine compartment. You will see some wiring to the housing and they plug into the resistor pak. The part is about $12 and available in parts stores. Failure is a common fault with this part.

Dave S(Texas)

ya I replaced the resistor and it fixed my problem, but let me tell you that getting that old resistor off and the connector apart took my almost 2 hours. I had to cut everything off, because the old resistor and connectors were rusted together. I did get it apart, but what should have been a 5 mins job took me 2 hours, because I didn't want to cut the wires. After that ordeal everything works fine and thanks for the info.

Where the pack located - engine compartment or under dash? Got a ranger w/ low fan speed out.

On Sat, 18 Nov 2006 05:40:30 -0800, Flasherly rearranged some electrons to form:

Usually under the dash,look on the air ducts for a rectangular port with several wires coming out of it. The resistor is mounted in the air duct so it will be cooled by air movement.

Thanks, Dave. Got a Haynes and will also look if it's included in there.

could be the switch, could be the resistor.

steve

ACTUALLY, they are usually on the engine side of the heater case next to the blower motor.

steve

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required