Starting the engine with a fully discharged battery
If, when the battery is completely discharged, an external power source is used to start the engine and the vehicle immediately starts moving (without giving a dead battery some time to recharge), interruptions in the ignition system may begin, which will lead to a stop of the car and the inability to continue driving.
This phenomenon occurs as a result of the high current consumption of the ABS system for self-diagnosis. to avoid this phenomenon, it is necessary to allow the battery to charge while the engine is idling.
Attention! Do not operate the vehicle when the anti-lock brake system is (ABS) disabled (for example, the connector of the ABS electronic control unit is disconnected), otherwise the vehicle's behavior during braking will be unstable.
Troubleshooting algorithm for troubleshooting
The phenomena described in the following table are not abnormal and do not indicate a malfunction.
Fault detection conditions may vary depending on the diagnostic code.
Checking DTCs
Read the DTC using the MUT-II or the ABS warning light.
Reading with the ABS warning lamp
Use a special tool to ground the lead (1) (diagnostic control output) diagnostic socket.
Stop the engine.
Turn on the brake light switch (hit the brake).
After carrying out steps from point 1. to point 3., turn on the ignition. Within 3 seconds after turning on the ignition, turn off the brake light switch (release the brake). Then, turn the brake light switch on and off a total of 10 times.
Note. If the operation of the ABS electronic control unit has stopped due to the operation of the safety function, it will not be possible to erase the fault codes.
Checking the hydraulic block
Attention! Before connecting (or shutdown) on the MUT-II, turn the ignition key to position «OFF» («OFF»)
Raise the car with a jack and install support stands under it in specially designed places or install the wheels to be checked on the drums of the brake stand.
Attention! During the test, the surfaces of the drum of the brake tester and the tire must be dry.
When testing the front brakes, apply the parking brake, and when testing the rear brakes, block the front wheels.
Release the parking brake lever and check the resistance to rotation (moment of resistance) on every wheel.
When using a brake tester, record the resistance forces at each wheel. Turn the ignition key to position «Off» («OFF») and connect the MUT-II.
Making sure that the shift lever (vehicles with manual transmission) or selector (cars with automatic transmission) is in neutral, start the engine.
Use MUT-II to power the actuator.
Note. During the drive test, the ABS warning lamp will be on and the anti-lock braking system control will be disabled.
Note. If the ABS system has been disabled by a safety function, the MUT-II drive test cannot be performed.
Turn the wheel by hand and check the change in braking force with the brake pedal depressed.
When using a brake tester, depress the brake pedal until the braking force reaches the values below, and check if the braking force decreases when the hydraulic unit drive is turned on to the values measured in step 2.
- Front wheel: 785–981 N.
- Rear wheel: 588–784 N.
If the test results are not satisfactory, remove the cause in accordance with «Diagnostic table».
After completing the test, turn the ignition key to position «Off» (OFF) and disconnect the MUT-II immediately.
Recharge for a fully discharged battery
If, when the battery is completely discharged, an external power source is used to start the engine and the vehicle immediately starts moving (without giving a dead battery some time to recharge), interruptions in the ignition system may begin, which will lead to a stop of the car and the inability to continue driving.
This phenomenon occurs as a result of the high current consumption of the ABS system for self-diagnosis. to avoid this phenomenon, it is necessary either to allow the battery to charge while the engine is idling, or to disable the ABS system by removing the fusible link from the ABS circuit. At the same time, the ABS warning lamp will light up.
After the battery is sufficiently charged, turn off the engine, reinstall the fuse (ABS chains) and start the engine again. At the same time, make sure that the ABS warning lamp is off