MJPVFL

I have had a 2003 Suburban LT for 11 years, 165k miles. Having a problem with the front blower motor. It has an Auto Climate Control system, the information screen works fine, I can cycle the blower speed up and down but the blower will not run regardless of setting. I have cold AC flowing out of all the vents, just no velocity. Rear Climate Control works fine. All fuses check good. Read about a Service Bulletin, but am not sure if it applies to me as it has been 10+ years and it is an Auto CC, not Manual CC. Have read about different potential culprits; Blower Housing, Blower Speed Control, Blower Motor Resistor, Blower Control Module - some of which are probably the same thing!!! I am not sure what to replace, can anyone help me diagnose it and tell me what to replace? It is starting to get HOT here in Florida...

{tpc}

I would take a stab at the resistor first. I would think that with some searching you could find info on how to check this (sounds like and easy check with a voltmeter).

If not that, speed control sounds like something to look into as well.

73shark

If it was the just the resistor, the blower would still work on Hi. Need to check the voltage at the blower. If 12V when on Hi, then the motor is Tango Uniform.

MJPVFL

Thanks! Am I checking the voltage while the blower is still connected with the engine running or just key in ACC? Sorry if that is a silly question, but I want to be sure...

73shark

You'll check w/ the conditions that the blower would normally be running. Either w/ the engine running and the blower On or the key in the Run position and the blower On.

MJPVFL

Ok....that was weird. Took down the plastic housing, untwisted the blower motor, laid it on the housing. Tried to seat the probes in the plug and take the readings but couldn't get the plugs to both stay in place (each would take turns popping out of place while I went to put the key in). Decided to check the condition of the plug before I forced the probes further into place. Disconnected the plug from the blower to check for corrosion, dirt, etc - saw nothing obvious. Reconnected the plug and then forced each probe into place. Leaned over, turned the key to the On position and the blower started going (was set at full speed); probe wires were flapping and flying! Pulled the wires out of place then took the key out. In those few seconds the blower had cut a notch into the plastic housing! Nice. Set the blower upright, turned the key On and the blower fired right up. Electronic speed control worked fine up and down. Blower is not as quiet as originally (I guess it is a little off balance from burning through the housing), but it is running. Reseated it and put the gouged out housing back in place. It runs. Will let it run for a day and see if the blower settles out, if not I'll pull it down again, check for obstructions and try to reseat it. I'm sure it won't work after I do that...the car gods are laughing.... Any ideas?!?