Ignition Off, Function - GF07.10-P-1002MRA

Engine 274.9 in model 205 (except 205.047/053/054/147/247/253) 

Engine 274.9 in model 253 (except 253.354/954) 

Function requirements for ignition OFF, general points 

• Circuit 87 M (engine management ON)
• Terminal 15

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 (N3/10).

Function sequence for ignition OFF 

With ignition OFF, the electronic ignition lock control unit (N73), via interior CAN (CAN B), and the front SAM control unit (N10/6) switch off the engine compartment circuit 15 relay (K40/8kG).

The "circuit 15 OFF" signal is sent redundantly from the electronic ignition lock control unit via the suspension FlexRay (Flex E) to the powertrain control unit (N127) and the drive train CAN (CAN C1) to the ME-SFI [ME] control unit.

If the ME-SFI [ME] control unit receives the "circuit 15 OFF" signal over the engine compartment circuit 15 relay, the engine is switched off by shutting off the fuel pump (M3), the fuel injectors (Y76/1 to T1/4) and the ignition coils of the cylinder 1 to ignition coils of cylinder 4 (T1/1 to Y76/4) are switched off and computer run-on is started.

The ground connection "circuit 31" takes place from the on-board electrical system battery (G1) over the battery ground point (W10) and over a number of ground lines to the left major assembly compartment electronics ground point (W16/5).

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".