3239519 - E7021 ASR / TCS - Functional description

Functional description

ABS electronic control unit M50 is supplied (at pins 2 and 6) directly by the battery via a line protected by the ABS maxifuse, located directly on the battery A1 - connector C. The supply controlled by the ignition (15/54) reaches pin 23 from the line protected by fuse F6 of the additional fuse box B98 A . The control unit is earthed via pins 1 and 5. The four sensors K70, K71, K75, K76 send wheel speed signals to pins 12-28, 16-15, 14-13 and 30-31 of M50 respectively. Brake pedal switch I30 sends a 'pedal depressed' enablement signal to pin 32 of control unit M50 : the ABS cannot intervene unless the brake pedal is pressed. The control unit M50 receives a 'pedal released' signal, always double switch, at pin 20. The 'ASR OFF' control button on panel H35 sends a deactivation signal to pin 28 of M50 , while pin 27 relays a signal that turns on an LED on panel H35 when the system is off. If the control unit M50 detects problems relating to the ABS function, it sends the speedometer instrument E10 a signal from pin 22, which lights up the 'ABS failure' warning light; the lighting up of the 'ASR' warning light is also managed via the same line; if the problems concern the EBD function, the handbrake warning light is lit up from pin 38 of M50 .; these are earth signals, and they cause the warning lights to come on because the instrument E10 supply is controlled by the ignition (INT) from the line protected by fuse F4 of the additional fuse box B99B . Pin 37 of M50 produces a speedometer signal (average speed of all four wheels) which is sent to the instrument panel E10 See E4021  SPEEDOMETER . The autodiagnostic data can be read by connecting to connector R10 : it receives signals from pin 11 of the control unit M50 via the special diagnostic line. The CAN line that connects M50 (from pins 24 and 40) to M10 allows the ASR function to notify the engine management control unit of excessive engine power; this line is not direct, but passes through the steering sensor K58 See E5030  PETROL ENGINE ELECTRONIC MANAGEMENT ,  See E5050  DIESEL ENGINES ELECTRONIC MANAGEMENT .