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

ENGINE 642.8 in MODEL 204 

ENGINE 642.8 in MODEL 207 up to 5/31/13, 212, 218 up to model year 2014 

Function requirements for ignition ON, general points 

• Circuit 15 ON

Ignition ON, general points 

With ignition ON, the engine timing in the CDI control unit (N3/9) 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) forwards the on-board voltage from "circuit 30" to "circuit 15" over the engine compartment circuit 15 relay (N10/1kJ).

If a voltage is present at the CDI control unit at "circuit 15", the 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 directed from "circuit 30" (downstream of respective fuses) as "circuit 87 M1" to the CDI control unit and to the corresponding sensors and actuators of the engine timing.

If a voltage is present at "circuit 87M1" the engine timing is switched on and an output stage driver in the CDI control unit applies actuation of the engine circuit 87 relay.

The "circuit 31" ground connection is made from the on-board electrical system battery (G1) via the front right battery ground point (W10) and via multiple ground lines to the left major assembly compartment electronics ground point (W16/5).

When the engine timing is switched on, the CDI control unit carries out the following functions:

• To ensure full flow, the fuel pump (M3) is actuated via the fuel pump relay (N10/2kD) (for model 207.3 up to 11/2009 and for model 212.0 up to 08/2009) (only at first ignition ON after unlocking the vehicle).
• To ensure full flow, the fuel pump is actuated by the fuel system control unit (N118) (model 204, model 207.3 as of 12/2009, model 207.4, 212.0 as of 09/2009, model 212.2, model 218) both directly and via the drive train CAN (CAN C) (only at first time ignition ON after unlocking the vehicle).
• In the instrument cluster (A1), the engine diagnosis indicator lamp (A1e58) is actuated for the lamp check by the CDI control unit via the chassis CAN (CAN E).
• Data are exchanged with the electronic ignition lock control unit (circuit 50 signal and drive authorization) via the chassis CAN.
• Actuation of the glow output stage (N14/3) via drive train LIN (LIN C1). The glow output stage then responds by actuating the glow plugs (R9) on the positive side. The preglow indicator lamp (A1e16) is actuated via the chassis CAN.
• The fault memory in the CDI control unit can be read out and cleared via the diagnostic CAN (CAN D) by means of the diagnostic connector (X11/4).
• Diagnosis can be carried out with Xentry Diagnostics through the diagnostic connector.
• The throttle valve actuator (M16/6) checks its return spring (by the position of the throttle valve) and adapts the position of the actuator, if necessary.

The messages for actuation of the engine diagnosis indicator lamp and the oil pressure warning lamp are received by the IC from the CDI control unit via the chassis CAN, routed by the front SAM control unit with fuse and relay module (N10/1), which receives the message on the chassis CAN from the CDI control unit.