1. Fuses: Check the fuses related to the wipers. Your owner's manual will show you the fuse box location and which fuses control the wipers (there might be separate fuses for low and high speed). Replace any blown fuses.
2. Wiper Switch: The wiper switch itself could be faulty. Try wiggling the switch while operating it to see if the wipers work intermittently. If so, the switch needs replacing.
3. Wiper Motor: The wiper motor might be malfunctioning. This is a more complex issue, potentially requiring professional diagnosis and replacement. Listen carefully – you might hear a clicking sound indicating a problem with the motor or its connection.
4. Wiper Linkage: The linkage connecting the motor to the wiper arms could be broken, dislodged, or seized. Visually inspect the linkage for any damage or obstructions.
5. Park Position: Ensure the wiper arms are not stuck in the park position. Sometimes they can get jammed. Gently try to move the arms (with the ignition off) to ensure they move freely.
6. Multifunction Switch (sometimes called a turn signal/wiper stalk): This is a common failure point on many vehicles. A faulty multifunction switch can interrupt power to the wipers.
7. Relay: There might be a relay involved in the wiper circuit. Your owner's manual or a wiring diagram might help you locate and test this. A faulty relay needs replacing.
8. Wiring: Check the wiring harness for any damage, especially where it connects to the motor and the switch. Look for breaks, corrosion, or loose connections.
9. Low Washer Fluid: While this won't directly stop the wipers, some systems have a sensor that prevents wiper operation if the fluid is low. Check your fluid level.
What to do:
* Start with the simplest checks: Fuses are the easiest to check and replace.
* Consult your owner's manual: This will provide specific information about your Avalanche's wiper system and fuse box layout.
* If you're not comfortable working on your car's electrical system: Take it to a qualified mechanic for diagnosis and repair.
If you've checked all these and the problem persists, it's best to consult a professional mechanic to diagnose the issue accurately and safely repair it.
