1. The Obvious:
* Empty fluid reservoir: Check the rear washer fluid reservoir (usually a smaller tank separate from the front windshield washer). It's easy to overlook.
* Frozen fluid: If it's cold outside, the fluid might be frozen. Try using a de-icer designed for washer fluid.
* Clogged nozzle: The nozzle itself might be clogged with debris. Try gently poking it with a thin needle or pin. Be careful not to break it.
2. More Involved Issues:
* Fuse: Check your owner's manual to locate the fuse for the rear washer system and check if it's blown. Replace it with a fuse of the same amperage if needed.
* Pump failure: The rear washer pump might have failed. This is a common problem. You'll likely need to access the pump (often under the rear cargo area) to check it. It might be a simple case of replacing the pump.
* Wiring issues: A broken or corroded wire in the wiring harness leading to the pump is possible. This requires tracing the wires to find a break or corrosion.
* Pump relay failure: The pump might be controlled by a relay. Check your owner's manual to see if there's a dedicated relay for the rear washer and test or replace it if necessary.
* Switch malfunction: The rear washer switch itself could be faulty. You might need to test the switch's continuity (if you have the tools) to confirm this.
Troubleshooting Steps:
1. Start with the easy stuff: Check the fluid level and nozzle first.
2. Check the fuse: This is a quick and easy step that often solves the problem.
3. Listen for the pump: When you activate the rear washer, can you hear the pump running? If not, the pump, relay or wiring is likely the culprit.
4. Visual inspection: If possible, visually inspect the pump and wiring for obvious damage.
5. Advanced troubleshooting: If you're not comfortable working with electrical systems, it's best to take your van to a mechanic.
Remember to always disconnect the battery's negative terminal before working with any electrical components in your vehicle. Safety first!
