Ignition ON, function - GF07.10-P-1000MMQ

ENGINE 276.8 in MODEL 207, 212 as of model year 2014

ENGINE 276.8 in MODEL 218 as of model year 2015

ENGINE 276.9 in MODEL 207, 212 (except 212.095), 218 as of model year 2014

Function requirements for ignition ON, general points

Terminal 30

Ignition ON, general points

For ignition ON, the engine management in the ME-SFI [ME] control unit (N3/10) is switched on and the engine prepared for starting.

Function sequence for ignition ON

When the ignition is switched on, the electronic ignition lock control unit (N73) operating via the interior CAN (CAN B) and the front SAM control unit with fuse and relay module (N10/1) actuates the circuit 15 relay (N10/1kJ). The signal "circuit 15 ON" is sent redundantly via the chassis CAN 1 (CAN E1) to the ME-SFI [ME] control unit. The circuit 15 relay passes the on-board electrical system voltage from "circuit 30" onto "circuit 15". If a voltage is present at the ME-SFI [ME] control unit at "circuit 15", engine circuit 87 relay (N10/1kN) is actuated by means of a ground signal.

This causes the relay to close its power contact and the voltage is forwarded from "circuit 30" (dependent on the respective fuses) as "circuit 87 M4" to the ME-SFI [ME] control unit and as "circuit 87 M1/2/3" to the respective sensors and actuators of the engine management.

If a voltage is present at "circuit 87 M4", the engine management is switched on and an output stage driver in the ME-SFI [ME] control unit takes over actuation of the engine circuit 87 relay.

The ground connection "circuit 31" is made from the on-board electrical system battery (G1) over the ground point battery at the front right (W10) and a number of ground lines to the ground point for the electronics assemblies compartment on the left (W16/5).

When the engine management is switched on, the ME-SFI [ME] control unit carries out the following functions:

To ensure full flow, the fuel pump (M3) is actuated by the fuel system control unit (N118) (both directly and via the drive train CAN (CAN C)) (only at first time ignition ON after unlocking the vehicle).
In the IC (A1) the engine diagnosis indicator lamp (A1e58) is actuated via chassis CAN 1 and chassis CAN 2 (CAN E2) for a lamp check.
Data are exchanged with the electronic ignition lock control unit (circuit 50 signal and drive authorization) over the chassis CAN 1.
The throttle valve actuator (M16/6) checks its return spring (by the position of the throttle valve) and may adjust the position of the actuator.
The fault memory in the ME-SFI [ME] control unit can be read out and deleted via the diagnostic connector (X11/4). The diagnostic connector is networked via chassis CAN 1 and diagnostic CAN (CAN D) with the ME-SFI [ME] control unit.
Correction programming or diagnosis can be carried out with the Xentry diagnostics over the diagnostic connector.

Different characteristics maps for the engine management can be stored and activated with the correction programming in the ME-SFI [ME] control unit, such as:

Ignition map for adaptation to various fuel grades (RON correction (R esearch-O ctane N umber))
Mixture maps for enriching the fuel/air mixture in different operating states
Basic setting for idle speed
Idle speed for engaged gear range
Fault setting conditions for smooth running detection
Temperature correction for switching on and off the internal combustion engine fan motor and air conditioning system with integrated control (M4/7)

Electrical function schematic, ignition ON	MODEL 207	PE07.10-P-2700-97EAK
	MODEL 212	PE07.10-P-2700-97DAQ
	MODEL 218	PE07.10-P-2700-97XAI
Overview of system components for gasoline injection and ignition system with direct injection	ENGINE 276.9 in MODEL 207, 212 (except 212.095), 218 as of model year 2014	GF07.70-P-9998MM
	ENGINE 276.8 in MODEL 207, 212 as of model year 2014 ENGINE 276.8 in MODEL 218 as of model year 2015	GF07.70-P-9998MMP