How to diagnose what is the problem?? NO A/C OR HEAT!!

[GotBonneBWitMe]

Hello all.

Been a while since I posted.

But I am back with another Bonneville!! I'll do a topic on it at a later date when I take pictures.

It is a 2000 SSEI. (First time having a newer one).

Now, I checked all fuses and relays. Relay #33 (Under hood) was missing, but I swapped it out with another similar relay. That didn't work (Unless it has a special type of relay?) Everything seems to be good in that area.

I tried tapping the blower motor but that didn't work neither.

Oddly, the ECC "adjusts" the fan speed by itself, but again, the blower motor doesn't work at all.

Could it be the resistor or motor or both?

How should I test everything out to get a precise answer?

Chicago is very bipolar now, could be 90 degrees tomorrow or even 40 degrees So I need this fixed ASAP.

Just need suggestions. Thanks!

[nos4blood70]

Resistors don't really go wrong in the 2000+s like they do in the 97-03 Grand Prixs. I would say that you need a new blower motor.

[bobgto65]

Check the voltage going to the blower motor at various speeds. If it is getting voltage (purple wire) and not working, you need a blower motor. If there is no voltage, the blower motor control module just to the left of the motor may be bad.