Had some electrical work to fix my radio and speakers. Got the car back, AC would not come on and AC indicator lights would not work. Took it back, guy said "my bad" put some plug back in. Took the car out and noticed AC would come on but only work on #4 setting. In a hurry and frustrated so I put up with it. Could this just be a loose connector or is something going on with the switch? I can pop out the whole assembly by myself but wanted to know anything I should look for? My dash lights don't work either in that panel (AC, hazard, defogger, etc.). Any help/feedback would be appreciated.

 

Page 2 in the FAQ's

There is a resistor assembly mounted on the air duct close to the blower motor. That part has failed. It is used to control fan speeds 1, 2, and 3. Speed 4 is the maximum blower motor speed, so no resistors are involved. Replacing the resistor assembly is something the home mechanic can do. The only tool needed is a Phillips screwdriver. The replacement part costs about US$30.

The blower motor is located just above the passenger's feet. Look at the wires leading away from the blower motor. Just inches away from the blower motor there is an electrical connector located on the air duct. That's the resistor assembly. It is easy to remove and replace.

Replacement is the usual remedy. However, if a spot of localized damage is seen it may be repaired with a soldering gun.

There is a good photo of the blower motor and resistor assembly in the Haynes repair manual, page 3-8. If you don't already have a copy of this book, please get one. It will be money well spent.

a) Move the front pass seat all the way back (for convenience)
b) Remove a harness connector (with 4 wires I think) running into the bottom of the blower motor.
c) Remove the 2 philips screws that hold the blower motor resistor in place.
d) Put new one in, reverse install.

Blower Motor Resistor Part Number: 27150-1E405

You can get it here for $30:

https://www.courtesyparts.com/oem-parts/nissan-resistor-271502j000

 

Same problem in my car! I've just been living with it, usually drive with the windows down now.
Maybe i'll replace it, but there are other parts i need that take priority over the fan speed right now.

 

Starts to make sense, the guy was messing with parts under the seat. I'll check the connector and see what's up. I have the Haynes manual. Thanks for the feedback.

 

 

Chances are the bearings (bushings actually) in the fan motor are worn out and binding, preventing the fan from spinning at full speed. The blower motors don't last forever. In the $40 range for a new one.