1. Blower Motor Relay issue:
* Check the blower motor relay. If it's stuck in the "on" position, it will keep the blower fan running even after the ignition is turned off.
* Test the relay by swapping it with a known-good relay.
* Replace the relay if needed.
2. Faulty Blower Motor Switch:
* Check the blower motor switch. If it's faulty, it may be sending a continuous power signal to the blower fan, even when it's turned off.
* Try turning the blower motor switch on and off a few times to see if it affects the fan's behavior.
* If the fan still won't turn off, the switch might need to be replaced.
3. Temperature Control Module Issue:
* Check the temperature control module (TCM). A malfunctioning TCM can cause the blower fan to run continuously.
* Perform diagnostics tests to identify any issues with the TCM.
4. Wiring Problem:
* Check the wiring between the blower motor, the blower motor relay, and the temperature control module. Look for any loose connections, damaged wires, or short circuits.
* If you find any wiring issues, repair or replace the affected wires.
Recommended Steps:
1. Check the blower motor relay:
* Locate the blower motor relay in your vehicle's fuse box.
* Remove the relay and inspect it for damage.
* If the relay is damaged, replace it with a new one.
2. Check the blower motor switch:
* Turn the ignition switch to the "Off" position.
* Turn the blower motor switch to the "Off" position.
* If the blower motor continues to run, the switch is faulty and needs to be replaced.
3. Check the temperature control module (TCM):
* Locate the Temperature Control Module (TCM) unit.
* Disconnect the electrical connectors from the TCM unit.
* If the blower motor stops running after disconnecting the TCM connectors, the TCM unit is faulty and needs to be replaced.
4. Check the wiring:
* Inspect the wiring for the blower motor, blower motor relay, and TCM.
* Look for any damaged wires, loose connections, or short circuits.
* Repair or replace any faulty wiring as necessary.
5. Seek professional help:
* If you're unable to diagnose and fix the problem on your own, it's best to take your vehicle to a qualified automotive technician for further diagnosis and repair.
