If the glass washer on the Mercedes-Benz C-class (W204) is working late (the caretaker is already moving and there is not a liquid supply yet), the non-return valve on the nozzle is most likely. It may be clogged by a non-quality cleaning fluid. There are several ways to solve the problem: Substitute for the non-return valve from another vehicle (e.g. from Opel, No. 1450650) to the nozzle.
- Replacing the assembly-out assembly with the original.
- Install the non-return valve from another vehicle (e.g. Opel, No. 1450650) in an incision with the hose on the nozzle.
- Inverting a normal non-return valve.
The failure may also be caused by the failure of the pump pump (some modifications the non-return valve is built into the pump).
