1. Power Supply Issues:
* Blown Fuse: Check the fuse(s) in the fuse box (usually under the hood and inside the vehicle) that control the blower motor. The owner's manual will show you which fuse(s) are responsible.
* Relay Failure: The blower motor often uses a relay to switch the high current. A bad relay will prevent the motor from receiving power. Locate and test the relay (often near the fuse box). You may need a multimeter to check for continuity.
* Wiring Problems: Look for broken, corroded, or loose wires in the wiring harness leading to the blower motor. This includes the connection at the blower motor itself. Pay close attention to the connector plugs. A visual inspection might reveal obvious problems, but a multimeter might be needed to test for voltage and continuity.
* Switch Malfunction: The blower motor switch itself could be faulty. Try different blower speeds to see if any work. If none work, the switch is a suspect.
2. Blower Motor Issues:
* Motor Failure: The blower motor itself might have burned out. This is a common failure point. You'll need to test the motor for continuity (with a multimeter). A failed motor usually needs replacement.
* Resistor Failure (if applicable): Some systems have a resistor pack that controls the different fan speeds. A faulty resistor can prevent the motor from working at all speeds, or only at certain speeds. This will need to be visually inspected and tested with a multimeter.
* Stuck Motor: Sometimes the motor can become mechanically stuck. You might be able to carefully attempt to free it, but this is risky and should only be done with caution.
3. Other Potential Problems:
* Grounding Issues: A poor ground connection can prevent the motor from receiving power. Check the ground wire connection to the chassis.
* Body Control Module (BCM) Issues (less likely): In some cases, a problem with the BCM could affect the blower motor. This is less common but should be considered if other steps fail.
Troubleshooting Steps:
1. Start with the easiest: Check the fuses first. This is the quickest and most common fix.
2. Use a multimeter: To effectively troubleshoot, you'll likely need a multimeter to test voltage, continuity, and resistance.
3. Consult a wiring diagram: A wiring diagram specific to your 1995 Chevy Tahoe will show you the correct fuse, relay, and wiring paths to the blower motor. You can often find these online (e.g., repair manuals, forums).
4. Access the blower motor: Accessing the blower motor often requires removing parts of the dashboard. Be careful and consult a repair manual or online guide for your specific vehicle model.
If you're not comfortable working with electrical systems, it's best to take your Tahoe to a qualified mechanic. Incorrect troubleshooting could lead to further damage.
