I changed the blower motor resistor on my 92 volvo 940GL and it didn't pop the fuse when I turned on the fan switch (which is a good thing) but the blower won't come on and I know the blower motor and the resistor are good. Any ideas on what to do next? Please help.

 

how do you know these things are good?

you could hook up 12V directly to the blower motor and verify spins, then you'd know it is in fact good.

I'd probably check the output of of the blower switch with a volt meter... lets see... battery power from the ignition switch goes to fuse 16, then fuse 16 goes to pin '1' of the blower motor switch on the smaller connector. the bigger connector, pin 4 is speed 1, pin 5 is speed 2, pin 3 is speed 3, pin 1 is speed 4, and pin 2 (back on the smaller connector) is speed 5.

speeds 1-4 are wired to the resistors the high speed 5 is a straight through wiring, red-white wire from the switch pin C2 goes to a passthrough on the resistor and comes out as red-white to the motor, +12V on this red-white wire should spin the motor at full speed.

with that and a volt meter it shouldn't be too hard to track down whats going on.

 

I know these things are good cause the blower motor and the resistor are brand new.

 

I've seen enough new stuff be bad that I no longer make that assumption.

I would be testing the voltage at the resistor pins when the fan is switched on. if there is voltage, then the problem is with the resistor pack, the fan motor, or the wiring interconnecting them or the ground. if there's no juice, then the problem is upstream, either the switch, its wiring, or the fuse.

 

I agree with Pierce. Check all electricals prior to installation. Take a look here for an example:

Volvo 240 Heater AC Blower Fan Motor Replacement

Here his new blower motor was missing one of the brushes.