Heater motor blowing nothing on #1, #2, #3 and blows about as hard on #4 as should be on #1. Replaced resister with new one ... not the problem. Got a blower motor from Junk Yard. hooked it up externally and same problem as before.

This losing some of the blower speeds is almost always the cabin blower switch. Remove the panel with the switch in it. There may be more than just that switch on the assembly. You may have to buy the whole assembly. Take a look at it.

AC fan doesn't work

COULD BE A BAD MOTOR OR A BAD SWITCH, OR EVEN A BAD GROUND

Sounds like either you have extra resistance in the circuit before the blowe rmotor or extra resistance after the blower motor.

With the blower motor plugged in check for voltage on the orange wire. There should be 12 volts. if there is less than 12 volts than you have extra resistance in the circuit before the blower motor. Lower voltage = lower fan speed.

If there is w12 volts on the orange wire check voltage on the black wire. You should see 0. If you see more than 0 than you have extra resistance in the ground circuit. Make sure your ground is good and clean.

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