S6 V8-4.2L (BBD) (2004)
Vacuum Pump: Description and Operation
Electric vacuum pump
Description and function
The electric vacuum pump is only installed in vehicles with automatic transmission. It is switched on by Engine Control Module (ECM) depending on
intake manifold pressure.
The vacuum pump is On Board Diagnostic (OBD) capable. Detected malfunctions are stored in Engine Control Module (ECM).
Testing function of electric vacuum pump via On Board Diagnostic (OBD) must only be performed with engine at standstill!