I have a 2002 TL with broken heat and AC. When I press the button to turn it on I can hear the compressor turn on which I think implies the relay is working. I checked the fuses and they are all fine. After searching the internet I found that many people had problems with the resistor and I ordered a new one because the old one was super corroded. Just now I have removed the blower motor itself and powered it with a drill battery and it works. When I turn the car on I get a constant 14v to the blower motor plug, which seems odd. Is this normal? Does anyone have any additional ideas as to what is wrong here? My searching has come up empty thus far. Any experience anybody has with this kind of issue would be helpful.

 

Just to make sure I am reading correctly - You are saying the blower won't run, but you have voltage on the blower motor plug, and the motor works when powered manually? That does seem odd. Here is what I would check:

- Run an HVAC diagnostics check. You'll need the service manual to interpret the code. I think you hold in Auto and Off buttons to run it. A segment in the LCD temp display will light up, and the manual will have the corresponding code and troubleshooting steps.

- Check all of the wiring for the blower under the dash. It is very common for the wiring to burn out. Check all connectors. Sounds like you replaced the resistor but make sure the connector is not damaged as well. On my TL, the connector to the blower motor burned out, so I spliced on a new connector and replaced the blower since the connector was damaged on the motor as well.

Good luck!