* Clogged Washer Jet: The most common culprit. The tiny nozzle that sprays the washer fluid might be clogged with debris, dried washer fluid, or even ice (depending on the climate). Try carefully probing the nozzle with a thin needle or compressed air to clear it.
* Broken Washer Pump: The pump that pushes the washer fluid to the nozzle might have failed. This is a relatively common failure point in older vehicles. You should hear the pump run when you activate the rear washer; if you don't, the pump is likely the problem.
* Low Washer Fluid: Sounds obvious, but it's worth checking. Make sure your washer fluid reservoir is full.
* Frozen Washer Fluid: If it's cold outside, the washer fluid might be frozen, preventing the pump from working or the fluid from flowing. Use a proper winter washer fluid.
* Vacuum Line Leak/Issue: Some systems use vacuum to activate the washer pump. A leak in the vacuum line could prevent the pump from receiving the signal to operate. This is less common but possible.
* Wiring Issue: A broken wire or loose connection in the wiring leading to the washer pump or nozzle could prevent it from functioning. This requires checking the wiring harness for damage or poor connections.
* Faulty Washer Motor Relay/Fuse: A blown fuse or a faulty relay could interrupt the power to the washer pump. Check your owner's manual to locate the appropriate fuse and relay and test them.
Troubleshooting Steps:
1. Check the fluid level: The simplest step first.
2. Listen for the pump: When you activate the rear washer, do you hear the pump running? No sound points to a pump problem.
3. Inspect the washer jet: Look for clogs and try to clear them.
4. Check fuses and relays: Refer to your owner's manual.
5. Visual inspection of wiring: Look for any obvious damage to the wires leading to the pump and nozzle.
If you've checked all of these and the problem persists, it's likely a more involved issue requiring professional diagnosis and repair, potentially involving the washer pump, vacuum lines, or wiring. A mechanic can pinpoint the exact problem more easily.
