A/C Blower Resistor
 

2000 Astro Van 4.3 L is having a problem with the high speed on the blower motor. Fan speed 1, 2 and 3 work, but high is out completely. Replaced the resistor with a new part and it worked for a day or two, then quit. It is getting power to the resistor and the relay clicks when it is moved to high speed but no blow. I rigged a wire from the battery to test the motor with full 12 Volts and it blows high speed. Why would it fry the high speed resistor, or do you think it was a faulty part?
Thanks

check resistor wires and connections. wire may have gotten hot, began to melt a bit.

All wires seem to be in tact with good connections.

I've only had to deal with the resistor once through all my vans. I'm with you guessing faulty part.

Found this thread through a search, having the exact problem. In my case, I do have a burnt plug on the fused 12V wire A to the resistor. When I saw it, I cleaned it up, filed, squeezed, and put some dielectic grease on the contact, apparently that wasn't good enough.

This has been the third one in 10 years. 118K, dealer put one in at right before 3 years, I put one in several years ago, now one this week. Same as OP, worked for a day this time, high went out.

I also have installed a generic blower motor perhaps a year ago. Was thinking of jumping it to the battery with an ammeter to see how much pull the fan has on high. Something caused the lead to melt.

Any more ideas?

Front Blower Motor Resistor
 

My high speed is out also, where is the resistor located? I want to replace it, thanks, Russell

Russell, pull your washer/radiator reservoir out, it'll be located in the AC housing behind the reservoir. It has a twin lead going to the blower motor, and IIRC, a 6 lead connector pugging into the resistor. It's not at all what I expected, about an inch high perhaps 4 inches across, with the resistor pack exposed to the air being circulated inside the AC housing I'm assuming for cooling.

An update on mine, a trip to the junkyard netted me a used connector and resistor for $15. Spliced in the connector, has been running fine for a month.

Paul

Resistor Change
 

Thanks for the help, now I know what to change.