OK, what did I do now? I removed the heater/radio fascia to put in a FM module for the SiriusXM radio,. After doing that, found that the heater fan will not turn on. What I've done:

1. Disconnected battery for >30min to reset anything that may need to be reset. No effect
2. Re-removed the fascia and checked all connections again. No Effect
3. Checked all fuses, found fuse 53 (heater control module) blown. Replaced and checked fan, still will not work. (Rechecked fuse, still good).
4. Checked all 4 positions of the fan switch, all dead. However, I hear a relay click behind the glovebox when I switch from position 3 to 4.


I've also noticed that when I reconnect the battery, and turn the ign to on, all three orange LED's flash and something in the heater box is moving (I.E.- calibrating or finding a home position).


So, other than getting a new heater control module, what should I check for next?

 

You didn't say what year your 3 is? Check your owner's manual. There are more than the 1 fuse for the system. My '08 manual shows: Fuse #53, 'Power Heater Switch', Fuse #59, 'Climate Control', Fuse #82, 'Climate Control Fan'. Since you're hearing the relay when you switch from position 3 to 4, it's obviously sending and receiving the signal. You're 'Climate Control Fan fuse could be the problem.

Edit: Just checked an '06 manual (I found your year 3 in your 'garage'). Looks like Fuse #82 is your blower fan.

 

Sorry, forgot to add that. Swapped 82 with the one next to it, no effect. Not sure if I checked the climate control fuse. Will check that tomorrow. Did a web search and it seems the main culprit could be the A/C-Heater resister. A $24 part at Advanced. I'll check with the dealer tomorrow as he repeatedly beats the 3rd party parts slingers prices.

 

The resistor you're talking about is what gives your fan speeds 1 thru 3. It's function is to reduce the voltage to the fan motor, down, to give you slower speeds. Speed 4 by-passes the resistor and gives you full 12v to the motor, so, if it's still not working on speed 4, I would say it's not your resistor.

 

Think I found my problem. The "blister" in both pics is the power wire connection. No power, no workie. It's past 10, I couldn't get it apart, but I'll order up a new resistor pack in the AM and get some crimp on connectors.

 

ya gotta get the message that it usually,rarely is the resistor!!!!!,,,its the melted connection!!!.
read ancient posts describing this problem starting 98 years ago!!!, well not quite that long.

lets all repeat,in unison,,"its not the resistor"!!




its usually the connector,,,really, a hundred guys have done the fix,not me, I JUST READ!!