The heater on my 1993 honda accord only works on 'High' or '5'. Could this be the heater relay? If so, where is this located? Also the blower motor/fan squeaks when the heat is on high.

I had the same thing happen on an old car. The blower was friction mounted and it would fall especially when the temperatures dropped. I would then go under the passenger compartment and push it up. No squeak.

There was a kit to fix it, but I had to eventually make my own.

The sqeaking took out the blower resitor and eventually the brushes in the blower motor. They are not available separately, so with the help of a vacuum cleaner store, I manufactured new brushes.

Sounds like the Blower Motor Resistor, which is located on top of the Air Box. When the Blower Motor Resistor goes bad, it only works on High.

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