How to Troubleshoot a heater blower motor
Basic instructions on how to troubleshoot the heater blower motor of a Saturn S-series. The heater blower motor is located behind the glove compartment of your vehicle. Disconnect the negative and positive power supply. (The black wire is usually the negative.) Using a multimeter set on the Ohm scale, use the positive lead and test the black wire. To check the purple wire for current, use your ignition key and turn it to the run setting, turn the heater power to full power and set the multimeter to DC power. If your meter reads "no current" the motor is no good. If it reads currents, further testing is required. Remove the fuse panel access cover which is located right near the shifter on the passengers side of the foot well. Remove the blower motor relay. Check the ground in the relay with the multi meter on the Ohm scale. Check the live current pin without grounding it on the DC scale of your multimeter. If you don't see current check the IGN fuse under the hood in your junction box. Remove the panel cover under the hood. Using a test light, connect it to the negative of the battery. If the fuse is not good, replace it. If the fuse works, you need to check the connector. Turn the ignition to run, test the connector with your multimeter on the DC scale. Check the HBAC 15 amp fuse with your multimeter. If all things work the most likely you need to change the relay. Once you have checked or replaced anything that wasn't working, it should be working just like brand new!