The blower motor does not turn at any setting. I've tried tapping on it with a screwdriver handle. Nothing. The fuses, relays, and the automatic climate control self-diagnostic test turned up no leads. I tested the power at the two wires that power the blower motor. Both have 12 volt power without the ventilation system being on. Is this correct? I ordered a new blower motor and don't want to burn it up when something upstream is funny.

The resistor looks ok.

I don't understand the wiring diagram in the Haynes manual. There are two leads to the blower. Should both be hot with just the ignition turned on?

 

It should have B+ to pin 1 (closest to the clip). Pin 2 should go to ground, but that's controlled by the AC/fan control amp. Set the fan speed to full, then check resistance from pin 2 to ground. Should be low.

Was the ignition switch in the ON position when you got B+ at both leads? Shouldn't be getting any power with the ignition off, or the key out.

 

Pin 1 on the blower motor connector has power. I tested the motor on the bench. It works. Does this point to the fan control amp?

I also found my FSM and am running through diagnostic procedure 7 in HA.

 

Turn on the climate control, fan on high, and check continuity from the pin 2 on the blower motor connector and ground. If you get no continuity, next thing I'd check is that amp.

 

With the fan setting on 4, I get negative numbers for resistance (for the different Ohm settings on my meter) from the blower motor connector number 2 pin. I also get continuity between blower pin 2 and fan control amp pin 1.

 

Check continuity between the fan control amp pin 3 and ground, then pin 2 and pin 35 of the AC auto amp. Either of those being open could cause the fan control amp to not work properly.

 

I replaced the Fan Control Amp part number 27761-70T03 and am back in business. The parts guy was sympathetic and only charged me $104.26 plus tax. I returned the unneeded blower motor to O'Reilly. I ran the fan cage through the dish washer while it was out.

 

My 1999 Maxima GLE doesnt blow at all in any speed either. Sometimes in a couple of days it blows again hot and cold. Which one would it most likely be, the amp or the resistor?? HEEELP!! Please thanks!

 

I had a situation where the blower motor wearing out was drawing excessive current from the fan control amp, causing it to overheat and pop the thermal overload built into it. I needed a quick fix (going on vacation in 2 days) so I had to bite the bullet and get a new amp from the dealer. Later research led me to also replace the blower, since that was probably the root of the problem. If your blower is very old, you may want to consider replacement before it takes out another amp...