Ignition ON, Function - GF07.10-P-1000MNB

Engine 178.9 In Model 190 

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 front SAM control unit with fuse and relay module (N10/1) is switched via the interior CAN (CAN B) by the electronic ignition lock control unit (N73).

The "circuit 15 ON" signal is sent redundantly from the electronic ignition lock control unit via the chassis CAN 1 (CAN E1) to the powertrain control unit (N127) and via the drive train CAN (CAN C1) to the ME-SFI [ME] control unit.

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

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 right major assembly compartment (W16/6).

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

• To prevent cylinder flooding, the fuel pump (M3) is actuated directly over the fuel system control unit (N118) and also by the FSCU via the drive train CAN (only the first time the ignition is switched ON after the vehicle is unlocked).
• In the IC (A1) the engine diagnosis indicator lamp (A1e58) is actuated via the engine CAN (CAN C), powertrain control unit, chassis CAN 1, electronic ignition lock control unit, interior CAN, AMG Gateway control unit (N93/9) and user interface-CAN (CAN HMI) for a lamp check.
• Data are exchanged with the electronic ignition lock control unit (circuit 50 signal and drive authorization) via the engine CAN, powertrain control unit and chassis CAN 1 (CAN).
• The left and right throttle valve actuators (M16/60, M16/61) check their return springs (via the position of the throttle valve) and adapt the positions, if necessary.
• 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 diagnostic CAN (CAN D) with the front SAM control unit with fuse and relay module, interior CAN, electronic ignition lock control unit, chassis CAN E1, powertrain control unit and drive train CAN 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 (Research-Octane Number))
• 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

	Electrical function schematic, ignition ON		PE07.10-P-2700-97HBA
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