303.02.0110 4-Circuit Protection Valve for DAF and Iveco

What does a 4-circuit protection valve do?

This pneumatic component serves as a critical safety element within the air brake system of heavy commercial vehicles. By receiving pressurized air from the compressor, it proportionally distributes supply pressure to four independent circuits. This ensures that even if a leak occurs in one circuit, the remaining sections remain functional to maintain braking performance.

Compatible vehicles and systems

The valve is compatible with DAF, Irisbus, Iveco, Nissan Ud Truck, Otokar, Renault Trucks, Van Hool, and VDL vehicles. It is specifically engineered to work within WABCO systems to provide consistent air distribution across the front axle, rear axle, spring brake, and auxiliary circuits.

Installation and maintenance

For reliable installation, ensure all connections utilize the specified M22x1,5 and M16x1,5 port configurations. Technicians should verify that the opening pressure of 7 BAR and closing pressure of 5 BAR aligns with the vehicle's pneumatic requirements during assembly to prevent system imbalance.

Troubleshooting and selection

Regular inspection of the valve housing and connection ports is recommended to identify potential leaks or debris that could interfere with the internal check valves. Consult your authorized distributor for more information.

OE cross-reference

303.02.0110 (4-circuit protection valve) is the equivalent of the DAF, Irisbus, Iveco, Nissan Ud Truck, Otokar, Renault Trucks, Van Hool, VDL and WABCO OE numbers. This part directly replaces DAF OE numbers 0644243, 0644243A, 0644243R, 0661690, 0661690A, 0661690R. It also replaces Irisbus OE number U403004456, Iveco OE numbers 04771458, 42008282, 500005444, 61598164, 61599534, Nissan Ud Truck OE number 066005380, Otokar OE number 9900005127AA, Renault Trucks OE number 5000504456, Van Hool OE number 637206380, VDL OE number 20194845 and WABCO OE number 9347023800.