This function is used to check every individual solenoid valve in the valve assemblies. Activate one valve at a time and listen for a hissing or clicking sound. The values are activated for a couple of seconds.
If no hissing or clicking sound is heard the valve may be defective or signal from the control module may be missing.
When a trailer is retrofitted it may be difficult to hear a hissing or clicking sound.
Test conditions:
Parking brake applied.
Working pressure in air system.
Battery voltage above 20 V
Procedure:
Start the function.
Select the valve to be activated.
Listen for a hissing or clicking sound.
Repeat the test for the other valves.
The function is done.
If the function fails, check the test conditions and repair any faults.