Here's a breakdown of what to check:
* Blower Motor Resistor: This is the most common culprit. It's usually located behind the glove box or under the dash. You'll need to consult a repair manual or online diagrams specific to your 1995 Chevy 1500 to find its exact location. Visually inspect it for any signs of burning or damage. If it looks suspect, it's likely the problem and needs replacement.
* Blower Motor: While less likely, a failing blower motor could also cause this issue. If the resistor is good, the next suspect is the motor itself. Testing it requires more advanced electrical knowledge or a multimeter.
* Wiring and Connections: Check all the wiring and connectors related to the blower motor and resistor for any loose connections, corrosion, or broken wires. A poor connection can disrupt the lower speed settings.
* Fuse: Although less probable given the symptom, it's worth checking the fuse related to the blower motor.
Troubleshooting Steps:
1. Locate the blower motor resistor: Use your owner's manual, a repair manual, or online resources to find its location in your specific vehicle model.
2. Visually inspect the resistor: Look for any signs of burning, melting, or damage. If it's visibly damaged, replace it.
3. Check the wiring and connections: Carefully inspect all wires and connectors for any problems. Clean any corrosion you find.
4. Check the blower motor (if the resistor is good): This requires more technical skills and tools. A malfunctioning blower motor might only allow the highest speed to work.
5. Replace the resistor: Once you've identified the faulty resistor (or suspect it's the problem), replace it with a new one. You can usually find these at auto parts stores.
Important Notes:
* Safety First: Always disconnect the negative battery terminal before working on any electrical components in your vehicle.
* Repair Manual: A repair manual specific to your 1995 Chevy 1500 will be invaluable in this process. It will provide detailed diagrams and instructions.
* Professional Help: If you're not comfortable working on your vehicle's electrical system, take it to a qualified mechanic.
The blower motor resistor is the most likely cause, and replacing it is relatively inexpensive and easy (though access can be tricky). Start there and work your way through the other possibilities if necessary.
