1. Identify the Problem:
* Wiper not working at all: This could be a blown fuse, a faulty motor, a wiring problem, or a bad wiper switch.
* Wiper working intermittently: Similar to above, but also points towards a potentially corroded connection or a failing motor.
* Wiper moving slowly or erratically: This usually indicates a worn-out motor, a problem with the wiper arm linkage, or a binding wiper arm.
* Wiper blade streaking or not cleaning properly: This is usually a simple fix involving cleaning or replacing the wiper blade.
2. Troubleshooting and Repair:
A. Check the Fuse:
* Consult your owner's manual to locate the rear wiper fuse. It's usually labeled clearly.
* Use a fuse tester or visually inspect the fuse for a blown filament (broken wire). Replace with a fuse of the same amperage if blown.
B. Inspect the Wiper Motor:
* Location: The motor is typically located under the rear cargo area trim panel. You might need to remove some panels to access it.
* Inspection: Check the motor connections for corrosion, loose wires, or broken wires. Clean any corrosion with a wire brush and electrical contact cleaner. Tighten any loose connections.
* Testing: If you have a multimeter, you can test the motor for continuity (resistance) according to the multimeter instructions. If the motor shows no continuity, it's likely faulty and needs replacement. This requires more advanced mechanical skills.
C. Check the Wiper Switch:
* This is usually located on the steering column. If the switch is faulty, it needs replacement (this is often more expensive than the motor). Testing the switch requires advanced knowledge and specialized tools.
D. Inspect the Wiper Arm and Linkage:
* Wiper Arm: Check for looseness, binding, or damage to the arm. Tighten any loose connections. If the arm is bent or damaged, it needs replacement.
* Linkage: Inspect the linkage mechanism for any broken or loose parts, corrosion, or binding. Lubricate any moving parts with silicone-based lubricant.
E. Replace the Wiper Blade:
* This is the simplest fix. Purchase a new rear wiper blade specifically for your 2005 GMC Yukon. Follow the instructions on the new blade's packaging for installation. Make sure the blade is firmly attached.
3. If the problem persists:
* Professional Help: If you're not comfortable troubleshooting electrical systems or mechanical parts, it's best to take your Yukon to a qualified mechanic. They have the tools and expertise to diagnose and repair the problem accurately.
Important Notes:
* Safety First: Always disconnect the negative battery terminal before working on any electrical components to prevent short circuits.
* Repair Manuals: A repair manual specific to your 2005 GMC Yukon will be extremely helpful in providing detailed diagrams and instructions for accessing and repairing the components mentioned above. You can find these online or at auto parts stores.
Remember to always refer to your owner's manual for specific information about your vehicle. By systematically checking these components, you should be able to pinpoint the cause of your rear wiper malfunction and repair it.
