1. Check Fuses and Relays:
* Locate the fuse box: Consult your owner's manual to find the location of the fuse box (usually under the hood or dashboard).
* Identify the wiper fuse(s) and relay(s): The manual should list the fuse and relay ratings for the windshield wipers. Carefully inspect them for any signs of damage (blown fuse, melted relay). Replace any faulty components. There might be more than one fuse or relay involved (e.g., one for high speed, one for low).
* Test the fuses: Use a multimeter to test the fuses' continuity.
2. Wiring and Connections:
* Inspect the wiring: Carefully examine all the wiring connecting the switch, motor, fuse box, and relay. Look for any broken, frayed, or corroded wires. Pay close attention to the connections – ensure they are secure and free of corrosion.
* Check the grounds: A poor ground connection can prevent the wipers from working. Locate the ground points for the wiper motor and the switch, and clean them thoroughly. Make sure they have a good, solid connection to the chassis.
* Trace the wiring harness: Follow the wiring harness from the switch to the motor and to the relay and fuse box. Look for any breaks, disconnections, or pinched wires along the way. This can be challenging, but a wiring diagram for your Thunderbird's year and model will be extremely helpful.
3. Wiper Linkage:
* Check the wiper linkage: Even with a working motor, problems with the linkage can prevent the wipers from moving. Manually try to move the wiper arms to see if they are free and operate smoothly. There might be a seized joint or broken part in the linkage. Repair or replace any damaged components.
4. Wiper Motor (Again!):
* Double-check the motor installation: While you've replaced the motor, ensure it's correctly installed and securely fastened. Incorrect polarity could damage it again, but usually the wipers simply won't move at all.
* Test the motor directly (advanced): This requires some electrical knowledge. If you have a 12V power supply and are comfortable working with car electrical systems, you could directly power the motor to verify it's working. *Important:* Connect the power supply correctly; otherwise, you could damage the motor. This step is risky if not done properly.
5. Consult a Repair Manual:
* A repair manual specific to your 1995 Thunderbird LX 4.6 will provide detailed wiring diagrams and troubleshooting steps. This is invaluable for pinpointing the exact location and function of all the components in the wiper system.
6. Seek Professional Help:
If you've exhausted the above steps and still can't identify the problem, it's best to seek assistance from a qualified auto mechanic. They have the experience and tools to diagnose and repair the issue efficiently.
Remember safety first! Disconnect the battery negative terminal before working on any electrical components. If you're not comfortable working with car electrical systems, it's safer to leave the job to a professional.
