Ignition On, Function - GF07.10-P-1000MNA

Engine 177.9 in model 205, 213, 253 

Function requirements, general 

• Circuit 30 ON

Ignition ON 

When circuit 15 is switched on (Ignition ON), the ME-SFI [ME] control unit (N3/10) starts the engine management and prepares the engine for starting.

The electronic ignition lock control unit (N73) sends the status of circuit 15 via interior CAN (CAN B) to the front SAM control unit (N10/6). The front SAM control unit actuates the engine compartment circuit 15 relay (K40/8kG). The engine compartment circuit 15 relay switches the battery voltage (circuit 30) to circuit 15.

The electronic ignition lock control unit also transmits the status of circuit 15 via the chassis FlexRay (Flex E), the powertrain control unit (N127) and the drive train CAN (CAN C1) to the ME-SFI [ME] control unit. The ME-SFI [ME] control unit then actuates the circuit 87M relay (K40/8kN). The circuit 87M relay switches the battery voltage (circuit 30) to circuit 87M. When circuit 87M is switched through to the ME-SFI [ME] control unit, it starts the engine management. A power amplifier driver in the ME-SFI [ME] control unit then takes over further actuation of the circuit 87Mrelay.

When it starts the engine management, the ME-SFI [ME] control unit carries out the following functions:

• Fuel supply

  The ME-SFI [ME] control unit transmits the switch on fuel pump (M3) request via a direct line and redundantly via the drive train CAN to the fuel system control unit (N118). The ME-SFI [ME] control unit also transmits the specified fuel pressure via the drive train CAN to the fuel system control unit. The fuel system control unit then correspondingly actuates the fuel pump.

• Function test

  The ME-SFI [ME] control unit checks the function of the left throttle valve actuator (M16/60) and the right throttle valve actuator (M16/61) and carries out actuator adaptation if necessary.