Central gateway control unit, task - GF00.19-P-4100-01SK

The central gateway control unit (N93) has the following tasks:

• Diagnosis gateway 

  The central gateway control unit (N93) bidirectionally routes the data between the control units connected to the respective Controller Area Network Bus Class B (interior) (CAN-B)/ Controller Area Network Bus Class C (engine compartment) (CAN-C) and the connected diagnosis tester (STAR DIAGNOSIS).

  This also applies to the other direction.

  There is an additional diagnosis identifier on the CAN-B, the global diagnosis request.

  The CAN-B control units are put into diagnosis mode simultaneously, irrespective of the circuit status. The global diagnosis request is transmitted to do this.

  On the CAN-C each control unit is put into diagnosis mode individually. The CAN-C control units are only active with circuit 15 on.

• Version coding 

  The equipment variants (countries, engine, etc.) are stored in the central gateway control unit (N93).

  These can be read out using the diagnosis and modified if necessary.

• Functional gateway between CAN-B, CAN-C and the diagnosis bus 

  The central gateway control unit (N93) forwards all the coding information such as the engine code and the national version to the relevant CAN-B and CAN-C control units via the network.

  The Service processor, the maintenance interval display and the system diagnosis are integrated into the central gateway control unit (N93) as independent modules and are treated as visual control units. This means that these control units are independent from a diagnostic point of view.

  The functional gateway messages are only transmitted on the CAN-C with circuit 15 on. All data that is needed by a control unit on the CAN-B is transmitted to the CAN-C and sent in the other direction if necessary.

• Data container 

  The data container in the central gateway control unit (N93) is a nonvolatile mobile data memory.

"Reverse gear" signal 

The "reverse gear" message on the CAN-B is identical for all transmission variants.

The automated manual transmission control unit (N15/6) (with transmission 722) transmits the "reverse gear" signal on the CAN-C.

With transmission 716 the "reverse gear" signal is discretely read in by the driver-side SAM control unit with fuse and relay module (N10/1) and put onto the CAN-B.

The central gateway control unit (N93) reads in the respective system and replaces it with a telegram that is transmitted on CAN-B.

"CRASH" signal 

The central gateway control unit (N93) reads in the "CRASH" signal from the rear SAM control unit with fuse and relay module (N10/2) and the ARMADA airbag control unit (N2/10). The central gateway control unit (N93) evaluates both signals and places the result on the CAN-C.