Usually no error is detected on the electronic air-processing units (EAPU) (1) which were replaced due to deposits of oil sludge (arrow) resulting from damage to the air compressor. The EAPU (1) is still fully functioning and is usually not defective as a result of visible oil sludge (arrow) and water. The oil sludge (arrow) is to be removed from the EAPU housing using a lint-free cloth. Afterwards, install a new granulate cartridge and check the cut-in pressure or shutoff pressure. If the EAPU is OK after this function check, it can remain installed in the vehicle.
If the granulate cartridge is replaced during maintenance and oil sludge (arrow) is found in the EAPU housing, the air compressor must be checked for oil discharge.
If metal shavings are visible in the EAPU housing when removing the oil sludge (arrow), the EAPU (1) must be replaced.
W42.60-A014-76
Check compressor for oil ejection | Model 963, 964 with engine 470.9 | ||
Model 956, 963, 964 with engine 936.9 | |||
Check cut-in and shutoff pressure of Electronic Air-Processing Unit (EAPU) | Model 956 | ||
Model 967 with code B1C (Electronic compressed-air supply unit, low) or with code B1D (Electronic compressed-air supply unit, medium) | |||
Model 963, 964 |