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GF07.61-P-3005MIS ME-SFI Ignition ON, Function



GF07.61-P-3005MIS ME-SFI Ignition ON, Function
- as of model year 09

Function requirements for ignition ON, general points
^ Circuit 15 ON

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

Ignition ON function sequence
When the ignition is switched on, the EIS control unit (N73) connects the on-board voltage from "circuit 30" to "circuit 15" via the circuit 15 relay (N10/1kD). If a voltage is present at ME-SFI [ME] control unit "circuit. 15", engine terminal 87 relay (N10/1kC) is actuated with a ground signal.

This causes the relay to close its power contact and the voltage is connected from "circuit. 30" (depending 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 actors of the engine control. If voltage is present at "circuit. 87 M4", the engine control is switched on and an output stage driver in the ME-SFI [ME] control unit takes over actuation of the engine terminal 87 relay.

The "circuit 31" ground connection takes place from the on-board electrical system battery (G1) via the battery ground (W10) and a number of ground lines to the electronic ground (footwell on the left) (W34/1).

When the engine control is switched on, the ME-SFI [ME] control unit carries out the following functions:
- For complete security, fuel pump (M3) is actuated by the fuel pump control unit (N118) (only the first time the ignition is switched ON after the vehicle is unlocked).
- The engine diagnosis indicator lamp (A1e58) in the ME-SFI [ME] control unit is actuated via the chassis CAN (CAN E) and central CAN (CAN F) in the instrument cluster (A1) for lamp check.
- Data are exchanged with the EIS control unit (circuit 50 signal and drive authorization) over the chassis CAN.
- The fault memory in the ME-SFI [ME] control unit can be read out and deleted through the data link connector (X11/4).
- Correction programming or diagnosis can be carried out with the Diagnosis Assistance System (DAS) through the data link connector.
- The throttle valve actuator (M16/6) checks its return spring (via the position of the throttle valve) and may lead to a positioner adaptation.
- The tumble flap switchover is actuated and the end position of the tumble flaps is checked.

The following partial functions which are active for ignition ON are described in the following documents:
^ ME-SFI [ME] fuel supply, function
^ Correction programming, function
^ ME tumble flap switchover function