Component Tests and General Diagnostics

A/C Blower Motor & Control System Diagnosis (Electrical).:

1. Possible location or cause of blower motor vibration are as follows:
a. Blower motor assembly loose in heater-A/C housing
b. Blower wheel loose on motor shaft
c. Blower wheel out of balance or bent
d. Blower motor defective
2. Possible location or cause of blower motor noise are as follows: (To verify blower noise disconnect blower motor wire lead connector and operate heater or A/C system. If noise goes away, proceed with procedure.)
a. Refer to vibration section of this procedure.
b. Foreign material in heater~A/C housing around blower wheel
c. Blower wheel rubbing heater-A/C housing
d. Blower motor defective