ECM (Main) Relay/Fuel Pump Relay

Control of the ECM and fuel pump relays is an output function of the MS41.1 Control Module. The operation is the same as the Bosch DME systems. When the ignition is switched "ON" (KL 15), the MS41.1 Control Module provides a ground for the control circuits of the two relays.

The ECM or main relay supplies operating power for the following MS41.1 components:
- MS41.1 Control Module
- Fuel Pump Relay
- Fuel Injectors
- Idle Speed Control Valve
- Transmission Control Module
- Evaporative Purge Valve
- Oxygen Sensor Heaters
- Exhaust Flap Solenoid
- Hot Film Air Mass Sensor
- VANOS Solenoid
- Air Pump Relay (Secondary Air Injection)
- Running Loss Solenoid
- Secondary Air Injection Solenoid

After the initial ignition ON input, the MS41.1 control module provides a ground for the fuel pump relay control circuit.
The circuit is maintained with the presence of the engine speed signal.
The fuel pump relay supplies operating power to the in-tank mounted fuel pump.