1. Verify the Fuse (Again, Thoroughly): Even if you checked it, double-check the correct fuse for the power door locks. Sometimes fuses can look good but have an internal break. Use a multimeter to test continuity.
2. Check the Door Lock Actuator:
* Access: You'll need to remove the interior door panel. There are many online tutorials specific to 1997 Chevy Lumina door panel removal – search "1997 Chevy Lumina door panel removal" on YouTube or a car repair site. Be careful not to break any plastic clips.
* Inspection: Once the panel is off, you'll see the door lock actuator. It's a small motor with linkages connecting it to the lock mechanism. Inspect for:
* Broken linkages: These are common points of failure. A broken or dislodged linkage prevents the actuator from moving the lock.
* Seized actuator: Try moving the actuator by hand. If it's stiff or doesn't move freely, it might be seized due to wear, corrosion, or lack of lubrication.
* Wiring: Examine the wiring harness connected to the actuator for any broken wires, loose connections, or corrosion. Wiggle the wires gently while observing if the lock moves – a sign of intermittent connection.
3. Test the Actuator:
* With a Multimeter: If you have a multimeter, you can test the actuator's motor for continuity and power when the lock is activated. This requires knowing the correct wiring colors and function (a wiring diagram would be helpful).
* Direct Power (Caution!): As a last resort, you can try applying 12V directly to the actuator's terminals (only if you know the correct polarity and are comfortable with car electrical systems). This is risky and could damage the actuator if done incorrectly. Use a low-current power source (like a small 12V battery) to test.
4. Wiring Harness Issues:
* Trace the Wiring: Follow the wiring harness from the actuator back to the main wiring loom inside the door and then to the body of the car. Look for breaks, chafing, or pinched wires anywhere along its path. The wires are often vulnerable to damage near the hinge area of the door.
* Continuity Test: Use a multimeter to test continuity in the wiring harness between the actuator and the body control module (BCM), the component that controls the power door locks. This will require a wiring diagram to identify the correct wires.
5. Consider Replacement:
* Actuator: If the actuator is broken or seized, it's usually cheaper and easier to replace it than to repair it. Auto parts stores will have replacement actuators for your Lumina.
* Lock Mechanism: If the problem lies within the lock mechanism itself (e.g., broken internal components), replacing the entire door lock assembly might be necessary.
Important Notes:
* Wiring Diagram: A wiring diagram specific to your 1997 Chevy Lumina is incredibly helpful for troubleshooting electrical issues. You can often find these online (repair manuals or forums) or at a parts store.
* Safety: Disconnect the negative battery cable before working with car electrical systems to prevent shorts and injury.
* Professional Help: If you're uncomfortable working on car electrical systems or are not able to identify the problem after these steps, consider taking your Lumina to a qualified mechanic.
Remember to search for specific 1997 Chevy Lumina repair videos or guides for more visual assistance with door panel removal and actuator replacement. Good luck!
