Components - ABS - Fiat DOBLO 1.9 JTD 8V da 12/03
| Component code | Description | Reference to the assembly |
| B001 | JUNCTION UNIT | |
| B2 | JUNCTION UNIT UNDER DASHBOARD | |
| C012 | ABS FRONT EARTH | |
| C15 | DASHBOARD EARTH, DRIVER''S SIDE | |
| E50 | INSTRUMENT PANEL | |
| H001 | IGNITION SWITCH | |
| I030 | BRAKE PEDAL SWITCH | |
| M001 | BODY COMPUTER | |
| K070 | LEFT FRONT WHEEL SENSOR FOR ABS | |
| K071 | RIGHT FRONT WHEEL SENSOR FOR ABS | |
| K075 | LEFT REAR WHEEL SENSOR FOR ABS | |
| K076 | RIGHT REAR WHEEL SENSOR FOR ABS | |
| M50 | ABS CONTROL UNIT |
| Component code | Description | Reference to the assembly |
| B001 | JUNCTION UNIT | |
| B2 | JUNCTION UNIT UNDER DASHBOARD | |
| C012 | ABS FRONT EARTH | |
| C15 | DASHBOARD EARTH, DRIVER''S SIDE | |
| E50 | INSTRUMENT PANEL | |
| H001 | IGNITION SWITCH | |
| I030 | BRAKE PEDAL SWITCH | |
| M001 | BODY COMPUTER | |
| K070 | LEFT FRONT WHEEL SENSOR FOR ABS | |
| K071 | RIGHT FRONT WHEEL SENSOR FOR ABS | |
| K075 | LEFT REAR WHEEL SENSOR FOR ABS | |
| K076 | RIGHT REAR WHEEL SENSOR FOR ABS | |
| M50 | ABS CONTROL UNIT |
The electronic antilock braking system regulates the braking pressure transmitted to the wheels, preventing them from losing grip whatever the tyre and road conditions.The system is designed to complement the conventional mechanical braking system and not to replace it, thereby guaranteeing effective safety in the case of problems: the system operates using the same brake fluid as in the conventional mechanical brake circuit.Four sensors, located on each of the four wheels, indicatae the speed of each wheel to the electronic control unit, recording any situations involving locking, slipping or loss of grip.If these situations occur, the electronic control unit operates solenoid valves, which modulate pressure in the hydraulic circuit to prevent lock and restore the vehicle to permissible grip limits to ensure the shortest possible stopping distance without losing control of the steering.Two regulation solenoids are fitted (a pressure charge solenoid and a pressure discharge solenoid) for each wheel.The sensors are active type, i.e. they consist of a receiver that faces a magnetic encoder built into in the hub bearing: under these conditions, the signal is less influenced by electromagnetic interferenced and temperature.In addition, the control unit manages distribution of the braking load over the rear axle to replace the mechanical load proportioning valve used previously (EBD function: Electronic Brake Distribution").The control unit is equipped with an autodiagnostic function: when an error is detected in the ABS function, it turns on the associated warning light and simultaneously deactivates the system: under these conditions the vehicle is braked using only the conventional braking system.When the control unit detects an error in the EBD function, it turns on the low brake fluid and handbrake warning light together with the ABS failure warning light.Under these conditions, the rear brake distributor control is deactivated and the vehicle must be driven with great caution.The power supply lines for the control unit and the various system components (sensors and actuators) are protected by two fuses located in the junction unit under the dashboard.
ABS electronic control unit M50 is supplied (pins 1 and 14) directly from the battery via two lines protected by fuses F5 and F4 in engine compartment junction unit B01.The control unit is earthed at pin 26.The four sensors K70, K71, K75, K76 send wheel speed signals respectively to pins 8-9, 6-5, 2-3, 11-12 of control unit M50.The normally open contact of brake pedal switch I30 sends an enablement signal to pin 16 of control unit M50 via a through line in under-dashboard junction unit B02.Brake pedal switch I030 is supplied by the ignition-operated (INT) line protected by fuse F37 of the underfacia junction unit B02:The ABS system cuts in if brake pedal I30 is pressed.The signal leaving I30 is the same one that turns on the brake lights.The ABS control unit is also supplied by an ignition-operated supply from a line protected by fuse F42 of B02 at pin 20 of control unit M50.If the ABS control unit identifies fault signals, it sends a signal from pin 10 to body computer M01 (pin 6 of connector C), which forwards the signal to control panel E50 to manage activation of the ABS fault warning light and, if the problems concern the EBD function, the low brake fluid and handbrake on warning lights.The body computer M01 receives a supply controlled by the ignition and a direct supply at pins 11 of connector E (INT) and pin A of connector C of under-dashboard junction unit B02 .The direct power supply is protected by fuse F1 in engine compartment junction unit B01.These lines also supply control panel E50, pins 1 and 3 of connector A (pins 1 and 2 of connector A for Natural Power versions), splitting inside under-dashboard junction unit B02 . These lines are protected by fuses F37 and F53.Pins 8 and 9 of connector E of the body computer M01 are earthed. This reference signal is also supplied to the panel via pin 36 of the body computer.The diagnostic line is connected to pin 1 connector B of body computer M01.
