Jim Grant's Tech Tips
‘97 Nissan Quest, A/C switch
Q: I have a ‘97 Quest Nissan van and it has a problem with the A/C switch and the air on the back that is not working. The A/C in the front is working fine. Could it be the fuse or something in the back switch is not working?
- Pearl N.
A: Depending on which climate control system your vehicle is equipped with there could be 1 or 2 fuses for the blower motor for the rear A/C. Of course, that should be the first check. If the fuses are good then diagnosis has to move to the connector for the blower motor. Nissan supplies power to the blower motor and that flow of power is controlled by the front or rear blower switch through a blower resistor for the rear blower motor. If there is no power to the blower motor and the fuses are good then check for a rear blower motor relay that may have failed. The more common failure we see is the blower resistor followed second by the blower motor. The likely hood of both the front and rear blower speed control switches failing is pretty slim. If you're not into diagnosing electrical systems, it is best to have a tech that has information (wiring diagrams) and is familiar with Nissan's climate control systems.