Ignition Off, Function - GF07.10-S-1002TRC

Engine 274 in model 447, 448 

except code XM0 (Facelift) 

Function requirements for ignition OFF, general points 

• Circuit 87M ON (Engine management ON)
• Circuit 15 ON

Ignition OFF, general points 

With the ignition OFF, first the engine and then the engine management are switched off in the ME-SFI [ME] control unit (N3/34).

Function sequence for ignition OFF 

For ignition OFF the electronic ignition lock (EZS) control unit (N73) sends the status of circuit 15 via the interior CAN (CAN B) to the signal acquisition and actuation module (SAM) control unit (N10/1). This reacts by switching off the circuit 15 relay (K40/10kR).

The signal "circuit 15 OFF" is sent redundantly via the chassis CAN (CAN E) to the ME-SFI [ME] control unit.

If the ME-SFI [ME] control unit (N3/34) receives the "Circuit 15 OFF" signal over the electronic ignition lock control unit (EZS) and the circuit 15 relay, the following components are switched off and the processor power-down is started:

• The fuel pump with fuel feed module (M3/6), to do this the ME-SFI [ME] control unit sends the "Fuel pump OFF" signal to the fuel system control unit (FSCU) (N118). This signal is sent redundant from the ME-SFI [ME] control unit as a CAN signal via the drive train CAN (CAN C) and as a ground signal. As a reaction the FSCU (FSCU) switches off the fuel pump with fill level sensor
• Fuel injectors (Y62)
• Ignition coils (T1)
• Quantity control valve (Y94)

If the computer run-on has ended, the circuit relay 87M (K40/10kN) is switched off and therefore the engine management.

The "circuit 31" ground connection is made from the on-board electrical system battery (G1) over the battery ground point (W10) and over several ground lines to the front right lamp unit ground point (W9).

When the ignition is OFF, the ME-SFI [ME] control unit is supplied with power from the on-board electrical system battery via "circuit 30 fused".