Symptoms of a Bad Blower Motor:
* No air from the vents: This is the most obvious sign. No matter what speed you select, no air comes out.
* Intermittent airflow: The blower works sometimes, but cuts out or changes speed unexpectedly. This is often indicative of a failing motor or a problem with the motor resistor.
* Blower motor runs at only one speed: If the blower only works on high speed (or only on low), the blower motor resistor is likely the culprit, not necessarily the motor itself, although a failing motor *could* cause this too.
* Loud noises from the blower motor: Grinding, whining, squeaking, or rattling noises coming from the blower motor housing usually point to a worn-out motor or internal bearing failure.
* Burning smell: A burning smell from the dashboard vents suggests a short circuit within the blower motor or its wiring. This is a serious issue and requires immediate attention.
How to troubleshoot:
1. Check the fuses and relays: A blown fuse or faulty relay can prevent the blower motor from working. Consult your owner's manual to locate the relevant fuses and relays for the HVAC system. Test them with a multimeter or by visually inspecting for blown fuses (broken filament).
2. Inspect the blower motor resistor: This component controls the blower motor's speed. A faulty resistor can result in only one speed working, or no airflow at all. It's usually located behind the glove box or under the dash. Access might require removing the glove box. Visual inspection for burn marks or obvious damage is a good start; testing with a multimeter may be necessary for a definitive diagnosis.
3. Check the blower motor switch: A faulty switch can also prevent the motor from working. Try different fan speed settings. If the problem is only with certain speeds, the switch might be the issue, but it's less likely than a resistor problem in producing a complete lack of airflow.
4. Listen to the blower motor: If you can access the blower motor (often requires removing parts of the dash), try turning the fan on and listen for noises. Unusual noises are a strong indicator of a bad motor.
5. Voltage test: Use a multimeter to check the voltage at the blower motor's connector. If there's no voltage, the problem is likely in the wiring or a previous component in the circuit. If there *is* voltage, but the motor doesn't run, the motor itself is likely the problem.
Important Note: Accessing the blower motor often requires removing parts of the dashboard, which can be challenging. If you're not comfortable working on your car's electrical system, it's best to take it to a qualified mechanic. Improper handling can lead to further damage.
