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

GF07.10-P-1000MMI Ignition ON, Function
ENGINES 152.9 in MODEL 172.4

Function requirements for ignition ON, general points
^ Terminal 30

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

Function sequence for ignition ON
Upon switching off of the ignition terminal 15 relay (N10/1kJ) is switched on by electronic ignition lock control unit (N73) via the interior CAN (CAN B) and by the front SAM control unit with fuse and relay module (N10/1). The signal "circuit 15 ON" is sent redundantly via the chassis CAN (CAN E) to the ME-SFI [ME] control unit. The circuit 15 relay conducts the on-board voltage from "circuit 30" to "circuit 15". If a voltage is present at the MESFI [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 connected from "circuit 30" (depending on the respective Terminal 30 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 timing.
If a voltage is present at "circuit 87 M4", the engine timing 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 "circuit 31" ground connection is made from the on-board electrical system battery (G1) via the battery ground point at the front right (W10) and over multiple ground lines to the right assembly compartment ground point (W16/4).

When engine timing is switched on, the ME-SFI [ME] control unit carries out the following functions:
- In order to provide full security, the fuel pump (M3) is actuated directly over the fuel system control unit (N118) and also by the FSCU via the drive train CAN (CAN C) (only the first time the ignition is switched ON after the vehicle is unlocked).
- In the instrument cluster (A1) the engine diagnosis indicator lamp (A1e58) is actuated via the chassis CAN for a lamp check.
- Data are exchanged with the electronic ignition lock control unit (circuit 50 signal and drive authorization) over the chassis CAN.
- The actuator motor (M16/6m1) in 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 the chassis CAN and diagnostic CAN (CAN D) with the ME-SFI [ME] control unit.
- Correction programming or diagnosis can be carried out with the Xentry diagnostics through the diagnostic connector.

Different characteristic maps for the engine timing can be stored and activated with the correction programming in the ME-SFI [ME] control unit, such as.
- Ignition maps for adapting the various fuel grades (RON correction (Research Octane Number))
- Mixture maps for enrichment of 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 combustion engine fan motor and air conditioning system with integrated control (M4/7)