1. The Fuses: This is the easiest and cheapest thing to check first. Consult your owner's manual to locate the fuse(s) for the wipers (there might be one for the motor and another for the intermittent function). Check for blown fuses – a broken filament inside will be visible. Replace any blown fuses with fuses of the *correct amperage*.
2. The Wiper Switch: The switch itself could be faulty. It's a common point of failure. Testing this often requires a multimeter to check for continuity (power flow) in different switch positions. A bad switch needs replacement.
3. The Wiper Motor: The motor itself might have burned out, seized up from age and corrosion, or have a faulty connection. This requires checking the motor's power supply (with a multimeter, being careful!) and potentially testing the motor itself (often involves removing it). A faulty motor requires replacement.
4. The Wiper Linkage: The mechanical linkage that connects the motor to the wiper arms could be broken, disconnected, or seized. This often involves visual inspection and sometimes lubrication (if seized). Broken parts require replacement.
5. The Wiper Motor Relay: Some vehicles use a relay to control the wiper motor. A failed relay will prevent the motor from working. This requires checking the relay visually for damage and potentially testing it with a multimeter. A faulty relay needs replacement.
6. Wiring Issues: Corrosion, broken wires, or loose connections in the wiring harness can interrupt power to the wipers. This often requires tracing the wiring harness from the switch to the motor, looking for any damage or loose connectors.
7. Low Washer Fluid: While it seems unrelated, some systems will not engage the wipers if the washer fluid reservoir is empty as a safety mechanism to prevent burning out the motor with no fluid to lubricate the wipers. Check the fluid level.
Troubleshooting Steps:
1. Start with the fuses. This is the easiest and quickest check.
2. Check the washer fluid level.
3. Visually inspect the wiper linkage. Are any parts broken or disconnected?
4. Check the wiper switch operation. Is it making proper contact?
5. If all else fails, you'll likely need a multimeter to check wiring and motor/relay power. This requires some electrical knowledge and is best left to a professional if you're uncomfortable with it.
If you're not comfortable working on your car's electrical system, it's best to take it to a mechanic for diagnosis and repair. Trying to diagnose electrical problems without proper tools and knowledge can lead to further damage.
