MODEL   215 with ENGINE 113, 137 (except 113.99)

P07.61-2159-09

Shown on example of Controller Area Network bus class C (engine compartment) (CAN-C) in model 220 with engine 112, 113 and code (219) Distronic (DTR) A1 Instrument cluster N3/10 ME-SFI [ME] control unit N15/3 ETC [EGS] control unit N15/5 Electronic selector lever module control unit N22 AAC [KLA] control and operating unit

N47 Traction systems control unit N51 AIRmatic with ADS control unit N63/1 DTR control unit N73 EIS [EZS] control unit N80 Steering column module

Task Data interchange between the individual control units Readying sensor signals for several systems Reducing the number of wires Improving the electromagnetic compatibility Design The data bus consists of a twisted, two-core data line which connects all the participants together in a parallel circuit. The data line lines must not be mixed up (low or high level). The ME-SFI [ME] control unit (N3/10) (except model 124 and model 140), the DAS [FBS] control unit (N73/1) (model 129), the DAS [FBS] radio frequency/infrared control unit (N54/4) (model 129) and the DAS [FBS] radio frequency control unit (N54/3) (model 170) are regarded as terminals as far as bus adaptation is concerned. A terminating resistor of 120 is fitted in each case. Exception: ME-SFI [ME] control unit (N3/10) with engine 120 (each fitted with 240 ). When measuring the resistance on the data line (circuit 15 OFF), the various terminating resistors in the terminals are connected in parallel.

Function The data are transmitted digitally on the data bus at various intervals. The individual data blocks are defined in a protocol and this also states which data are received or transmitted by a control unit. Each connected control unit is able to transmit or receive data. The total of the data blocks, the short pause between 2 transmission intervals and further properties of the data bus are checked constantly. Any faults detected are stored. Vehicles with EIS [EZS] control unit (N73) In the vehicle a distinction is made between a fast Controller Area Network bus class C (engine compartment) (CAN-C) and Controller Area Network bus class B (interior) (CAN-B) which is 6 times slower. The EIS [EZS] control unit (N73) forms the interface (Gateway) for this. This does not apply to vehicles with a central gateway control unit (N93) (except model 203).

Vehicles with central gateway control unit (N93) The central gateway control unit forms the interface (Gateway) between the two data buses (N93) (except model 203). The central gateway control unit (N93) serves as the interface for STAR DIAGNOSIS for all model series.

The new control unit must be coded again when exchanging a control unit. The control unit can be coded via a menu in the handheld tester (up to 07/99) or via STAR DIAGNOSIS.

	CAN data bus, function		GF54.00-P-0005A
	Extended vehicle networking (EVN), function	up to 31.8.03	GF00.19-P-0001S
		as of 1.9.03	GF00.19-P-0001SX