1. The sound of the system health check.
After starting the engine, sometimes a dull sound can be heard from the engine compartment. This is a sign that the control procedures for checking the performance of the ABS system are being carried out.
2. Sounds of the ABS system.
A) The sound of the pump motor running inside the ABS hydraulic unit (howling sound).
b) Sound accompanied by brake pedal vibration (scraping).
V) Sounds in the chassis of the car as a result of the periodic pressing and releasing the brake pedal.
Note: Undercarriage thuds usually come from the suspension and squeaks from the tires.
3. ABS system operation (long stopping distance).
On gravel and snowy roads, the stopping distance of a vehicle with ABS may sometimes exceed that of a vehicle with standard brakes. Therefore, it is recommended that drivers not be overconfident and, for safety reasons, slow down when driving on such roads.
Attention:
- The ABS system may work even if you do not brake hard when turning the steering wheel at high speed, when driving on a road with low traction, or driving on uneven surfaces.
4. Feeling of vibration on the brake pedal.
Vibration in the brake pedal is due to the activation of the ABS solenoid valves and is a sign of normal ABS system operation.
Checking the indicator "ABS"
1. Turn the ignition key to position "ON" and make sure the indicator "ABS" lit up for three seconds and went out.
2. Turn the ignition key to position "START" (START) to start the engine and make sure the indicator "ABS" lit.
3. Move the key in the ignition lock from position "START" (START) into position "ON" and make sure the indicator "ABS" lights up for three seconds and then goes out.
Attention: indicator "ABS" may burn after the key is returned to the position "ON" until the vehicle speed reaches 8-10 km/h. This situation is only possible if fault codes No. 21 - 24, No. 41 - 44, No. 53 - No. 55 were recorded in the memory of the ABS electronic control unit due to a previous malfunction. In this case, the ABS ECU will leave the indicator on until a check is made to confirm that the fault associated with this code has been repaired or self-repaired.
4. If the nature of the indicator "ABS" different from the above, check for trouble codes.
Models with standard instrument cluster.
Models with high contrast instrument cluster.
Reading trouble codes with a tester
1. Set the key in the ignition switch to position "OFF".
2. Connect a tester to a diagnostic socket under the panel of devices and read codes of malfunctions. Attention: follow the instructions for using the tester.
3. Determine the malfunction by reading the code and make the necessary repairs or troubleshooting (see table "ABS system fault codes").
Note: If the ABS system is not working properly and diagnostic codes are displayed, first check the cause given in the code description, then check that there is no malfunction (bad contact) in the connector or an open in the wiring harness. If no problem is found, substitute a known-good ABS ECU, then clear the codes and perform a road test.
4. After completing the repair or correcting the malfunction, turn the key in the ignition switch to the position "OFF".
Table. Codes of malfunctions of system ABS.
5. Delete trouble codes from the memory of the electronic control unit using the reset button of the tester.
6. Make sure there are no trouble codes.
7. Disconnect the tester from the diagnostic connector.
Reading fault codes without a tester
1. Set the key in the ignition switch to position "OFF".
2. Using a special test lead, connect the lead "DOT" diagnostic connector with ground.
3. Set the key in the ignition switch to position "ON" and read fault codes by the number of blinks of the indicator "ABS".
Note:
- The fault code consists of two digits, the first digit is determined by the initial series of flashes, then after a pause of two seconds, a second series of flashes follows, which corresponds to the second digit of the code.
- If there are two or more fault codes, the smallest code will be displayed first, and then the rest in ascending order. There will be a 3 second pause between codes.
4. If there is no fault, the indicator will flash at 0.25 second intervals.
5. Determine the malfunction by reading the code and make the necessary repairs or troubleshooting (see table "ABS system fault codes").
Note:
- If the ABS system is not working properly and diagnostic codes are displayed, first check the cause given in the code description, then check for a malfunction (bad contact) in the connector or an open in the wiring harness. If no fault is found, replace the integrated ABS unit (ABS electronic control unit) known to be good, then clear the codes and perform a road test.
- Diagnostic code No. 16 is erased from the memory of the integrated ABS unit (ABS electronic control unit), if the ignition key is turned to the "ACC" or if the system returns to a healthy state.
- Diagnostic codes No. 52 and No. 63 are erased from the memory of the integrated ABS unit (ABS electronic control unit), if the ignition key is turned to the "ACC".
6. After completing the repair or correcting the malfunction, turn the key in the ignition switch to the position "OFF".
7. Delete trouble codes from the memory of the electronic control unit (see subsection "Deleting fault codes without a tester").
8. Make sure there are no trouble codes.
9. Disconnect the special wire from the output "DCT" diagnostic connector.
Deleting fault codes without a tester
Deleting codes using the brake pedal (Pajero Sport)
Attention: if the ABS function is disabled (emergency operation of the ABS system), then the fault codes from the memory of the ABS control unit cannot be deleted by this method.
1. Set the key in the ignition switch to position "OFF".
2. Using a special test lead, connect the lead "DCT" diagnostic connector with ground.
3. Press the brake pedal (set the brake light switch to position "ON" (ON)).
4. Turn the ignition key to position "ON". Release the brake pedal within 3 seconds after turning on the ignition (set the brake light switch to position "OFF"
(OFF)). Then sequentially press and release the brake pedal ten times in a row (see picture "The diagram of the operation of indicators when deleting fault codes of the ABS system using the brake pedal").
The diagram of the operation of indicators when deleting fault codes of the ABS system using the brake pedal.
Note: When the trouble code clearing mode is activated, the ABS indicator will light up".
Removing codes by disconnecting the cable from the battery
Disconnect the cable from the negative battery terminal for 10 seconds or more, then reconnect the cable.
Checking the actuators of the hydraulic unit using a tester
1. To force the actuator to turn on, use the function "ACTUATOR TEST" tester.
Attention:
- The actuator test cannot be performed if the emergency mode of the ABS system is activated, or the vehicle is moving. If the speed of one of the wheels exceeds 10 km/h, then the check of the actuators will be terminated automatically.
- If the ABS indicator starts flashing, then it is necessary to stop checking the actuators.
2. When the ABS solenoid valve is activated (FR, FL, RR, RL) for each channel of the hydraulic block, except for the valve itself, the pump motor will be activated.
Checks on the connector of the ABS control unit
Checking the voltage at the terminals of the connector of the ABS electronic control unit
Attention: it is not allowed to measure the voltage at the terminals of the ABS electronic control unit within three seconds after the ignition is turned on, since during this period the initial check of the ABS system is carried out by the self-diagnosis system.
1. Rotate the latch as shown.
2. Press the tabs and disconnect the connector.
3. Check the voltage between the terminals "masses" ABS control unit and other outputs of the unit when the connector is connected (see table "Checking the voltage at the terminals of the connector of the ABS electronic control unit").
Checking the condition of the circuit and resistance at the terminals of the wire harness connector
1. Before starting to check the condition of the circuit and resistance, turn the key in the ignition switch to the position "OFF" (OFF) and disconnect the connectors of the ABS electronic control unit.
2. Check the voltage between the terminals of the connectors on the side of the wiring harness (see table "Checking at the terminals of the wiring harness connector").