08 expedition King ranch El rear AC

[joshterry94]

I have a 08 expedition king ranch EL with rear A/C issues with the blower motor not turning on. I have replaced the rear resistor because I believed the rear was bad. I can hear my relays clicking with different speeds selected. I have checked the ohms of the motor and seem to good. I have checked my voltage to the blower motor and have 13.5 vdc to it. So for trouble shooting I pulled the front blower motor out and brought it to the back( because front works) and installed wires into the plug and put them on the blower and it will still not turn.

I don’t understand I have the voltage there and neither blower will operate.

 

[S20Workstation4]

I had a similar problem about 1 year ago, and it turned out that the rear blower was having trouble with the copper brushes connecting to the motor (Inside the blower itself). I had to wack the blower with the end of a screwdriver a couple of times, and it would start working again, but die a couple of days later. I must have wacked it hard enough once because it hasn't broken on me in 9 months. Try hitting the blower (not an excessive hit) with something, while having the fan speed set to maximum. See if it starts spinning then.

One possible reason why the front blower motor might not be working in the rear HVAC system is because the front is a bigger blower and needs to run on its specified circuit.

Hope this helps,
-Joseph