Problem Symptoms Table
If there are no DTCs but the problem still occurs, check the circuits for each problem symptom in the order given in the table below and proceed to the relevant troubleshooting information.
NOTE:
When replacing the brake booster with master cylinder (skid control ECU), sensor, etc., make sure that the power switch is turned off, the stop light switch is off, and 2 minutes have elapsed since the driver's door was closed.
HINT:
- Since the hydraulic passage is blocked off by the master cut solenoid during electronically controlled brake system control, there is no kickback (vibration) to the brake pedal, creating a quiet sound even while the ABS is operating.
- Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
- Inspect the fuses and relays related to this system before inspecting the suspected areas below.
ELECTRONICALLY CONTROLLED BRAKE SYSTEM
| Symptom | Suspected Area | See |
|---|---|---|
| ABS, BA and/or EBD does not operate | Use a chassis dynamometer, etc. to check the electronically controlled brake system operation. | - |
| Check the DTC again and make sure that the normal system code is output. | Refer to DTC CHECK / CLEAR | |
| IG power source circuit | Refer to DTC C1241/41: Low Battery Positive Voltage; DTC C1242/42: Open in IG1 / IG2 Power Source Circuit | |
| Front speed sensor circuit | Refer to DTC C1271/71: Low Output Signal of Front Speed Sensor RH (Test Mode DTC); DTC C1272/72: Low Output Signal of Front Speed Sensor LH (Test Mode DTC); DTC C1464/31: Front Speed Sensor RH Circuit; DTC C1465/32: Front Speed Sensor LH Circuit | |
| Rear speed sensor circuit | Refer to DTC C1273/73: Low Output Signal of Rear Speed Sensor RH (Test Mode DTC); DTC C1274/74: Low Output Signal of Rear Speed Sensor LH (Test Mode DTC); DTC C1466/33: Rear Speed Sensor RH Circuit; DTC C1467/34: Rear Speed Sensor LH Circuit | |
| Check the brake booster with master cylinder (brake actuator) using the Techstream. (Check brake booster with master cylinder (brake actuator) operation using the Active Test function.) If abnormal, check the hydraulic circuit for leaks. | Refer to ON-VEHICLE INSPECTION | |
| If the symptoms still occur even after the above circuits in suspected areas have been inspected and proved to be normal, replace the brake booster with master cylinder (skid control ECU). | Refer to REMOVAL | |
| ABS, BA and/or EBD does not operate efficiently | Check the DTC again and make sure that the normal system code is output. | Refer to DTC CHECK / CLEAR |
| Front speed sensor circuit | Refer to DTC C1271/71: Low Output Signal of Front Speed Sensor RH (Test Mode DTC); DTC C1272/72: Low Output Signal of Front Speed Sensor LH (Test Mode DTC); DTC C1464/31: Front Speed Sensor RH Circuit; DTC C1465/32: Front Speed Sensor LH Circuit | |
| Rear speed sensor circuit | Refer to DTC C1273/73: Low Output Signal of Rear Speed Sensor RH (Test Mode DTC); DTC C1274/74: Low Output Signal of Rear Speed Sensor LH (Test Mode DTC); DTC C1466/33: Rear Speed Sensor RH Circuit; DTC C1467/34: Rear Speed Sensor LH Circuit | |
| Check the brake booster with master cylinder (brake actuator) using the Techstream. (Check brake booster with master cylinder (brake actuator) operation using the Active Test function.) If abnormal, check the hydraulic circuit for leaks. | Refer to ON-VEHICLE INSPECTION | |
| If the symptoms still occur even after the above circuits in suspected areas have been inspected and proved to be normal, replace the brake booster with master cylinder (skid control ECU). | Refer to REMOVAL | |
| ABS warning light abnormal (Remains on) | ABS warning light circuit | Refer to ABS Warning Light Remains ON |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| ABS warning light abnormal (Does not come on) | ABS warning light circuit | Refer to ABS Warning Light does not Come ON |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| Brake warning light / red (malfunction) abnormal (Remains on) | Brake fluid level warning switch circuit | Refer to DTC C1202/68: Master Reservoir Level Malfunction |
| Brake warning light / red (malfunction) circuit | Refer to Brake Warning Light Remains ON | |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| Brake warning light / red (malfunction) abnormal (Does not come on) | Brake warning light / red (malfunction) circuit | Refer to Brake Warning Light does not Come ON |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| VSC and/or TRAC does not operate | Check that traction control has not operated by carrying out diagnosis. | - |
| Check the DTC again and make sure that the normal system code is output. | Refer to DTC CHECK / CLEAR | |
| IG power source circuit | Refer to DTC C1241/41: Low Battery Positive Voltage; DTC C1242/42: Open in IG1 / IG2 Power Source Circuit | |
| Check the hydraulic circuit for leaks. | - | |
| Front speed sensor circuit | Refer to DTC C1271/71: Low Output Signal of Front Speed Sensor RH (Test Mode DTC); DTC C1272/72: Low Output Signal of Front Speed Sensor LH (Test Mode DTC); DTC C1464/31: Front Speed Sensor RH Circuit; DTC C1465/32: Front Speed Sensor LH Circuit | |
| Rear speed sensor circuit | Refer to DTC C1273/73: Low Output Signal of Rear Speed Sensor RH (Test Mode DTC); DTC C1274/74: Low Output Signal of Rear Speed Sensor LH (Test Mode DTC); DTC C1466/33: Rear Speed Sensor RH Circuit; DTC C1467/34: Rear Speed Sensor LH Circuit | |
| Yaw rate and acceleration sensor circuit | Refer to DTC C1234/34: Yaw Rate Sensor Malfunction; DTC C1243/43: Acceleration Sensor Stuck Malfunction; DTC C1244/44: Open or Short in Acceleration Sensor Circuit; DTC C1245/45: Acceleration Sensor Output Malfunction; DTC C1279/79: Acceleration Sensor Output Voltage Malfunction (Test Mode DTC); DTC C1381/97: Acceleration Sensor Power Supply Voltage Malfunction | |
| Steering angle sensor circuit | Refer to DTC C1231/31: Steering Angle Sensor Circuit Malfunction | |
| If the symptoms still occur even after the above circuits in suspected areas have been inspected and proved to be normal, replace the brake booster with master cylinder (skid control ECU). | Refer to REMOVAL | |
| Brake warning light / yellow (minor malfunction) abnormal (Remains on) | Brake warning light / yellow (minor malfunction) circuit | Refer to Brake Control Warning Light Remains ON |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| Brake warning light / yellow (minor malfunction) abnormal (Does not come on) | Brake warning light / yellow (minor malfunction) circuit | Refer to Brake Control Warning Light does not Come ON |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| Slip indicator light abnormal (Remains on) | Slip indicator light circuit | Refer to Slip Indicator Light Remains ON |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| Slip indicator light abnormal (Does not come on) | Slip indicator light circuit | Refer to Slip Indicator Light does not Come ON |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| DTC check cannot be done | Check the DTC again and make sure that the normal system code is output. | Refer to DTC CHECK / CLEAR |
| TC and CG terminal circuit | Refer to TC and CG Terminal Circuit | |
| If the symptoms still occur even after the above circuit in suspected areas has been inspected and proved to be normal, replace the brake booster with master cylinder (skid control ECU). | Refer to REMOVAL | |
| Sensor check cannot be done | TS and CG terminal circuit | Refer to TS and CG Terminal Circuit |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| Meter buzzer abnormal | Meter buzzer circuit | Refer to HOW TO PROCEED WITH TROUBLESHOOTING |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL | |
| Skid control buzzer abnormal*1 | Skid control buzzer circuit | Refer to Skid Control Buzzer Circuit |
| Brake booster with master cylinder (Skid control ECU) | Refer to REMOVAL |
*1: w/ Dynamic Radar Cruise Control System