Tech Tips
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.
Note
When replacing the brake actuator assembly, sensor, etc., turn the ignition switch off.
| Symptom | Suspected Area | See page |
|---|---|---|
| ABS, BA and/or EBD does not operate | Check again to see if DTCs are output. (If DTCs are output, perform diagnosis based on the DTCs that are output.) | |
| Power source circuit (low power supply voltage malfunction) | ||
| Power source circuit (high power supply voltage malfunction) | ||
| Front speed sensor circuit | ||
| Rear speed sensor circuit | ||
| Check the brake actuator assembly using the GTS. (Check brake actuator assembly operation using the Active Test function.) If abnormal, check the hydraulic circuit for leaks. | ||
| If the symptoms still occur even after the above suspected areas have been inspected and proved to be normal, replace the skid control ECU (Brake actuator assembly). | ||
| ABS, BA and/or EBD does not operate normally | Check again to see if DTCs are output. (If DTCs are output, perform diagnosis based on the DTCs that are output.) | |
| Front speed sensor circuit | ||
| Rear speed sensor circuit | ||
| Stop light switch circuit (on stuck malfunction) | ||
| Stop light switch circuit (open malfunction) | ||
| Stop light switch circuit (off stuck malfunction) | ||
| Check the brake actuator assembly using the GTS. (Check brake actuator assembly operation using the Active Test function.) If abnormal, check the hydraulic circuit for leaks. | ||
| If the symptoms still occur even after the above circuits in suspected areas are inspected and prove to be normal, replace the skid control ECU (brake actuator assembly). | ||
| ABS sensor DTC check cannot be performed | Check again to see if DTCs are output. (If DTCs are output, perform diagnosis based on the DTCs that are output.) | |
| TC and CG terminal circuit | ||
| If the symptoms still occur even after the above suspected areas have been inspected and proved to be normal, replace the skid control ECU (Brake actuator assembly). | ||
| ABS warning light abnormal (Remains on) | ABS warning light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| ABS warning light abnormal (Does not come on) | ABS warning light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| Brake warning light abnormal (Remains on) | Brake warning light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| Brake warning light abnormal (Does not come on) | Brake warning light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| VSC and/or TRC does not operate | Check again to see if DTCs are output. (If DTCs are output, perform diagnosis based on the DTCs that are output.) | |
| Check system variant learning. | ||
| Check the engine control system. | ||
| Power source circuit (low power supply voltage malfunction) | ||
| Power source circuit (high power supply voltage malfunction) | ||
| Check the hydraulic circuit for leakage. | - | |
| Front speed sensor circuit | ||
| Rear speed sensor circuit | ||
| Yaw rate and acceleration sensor circuit (sensor malfunction) | ||
| Yaw rate and acceleration sensor circuit (power supply voltage malfunction) | ||
| Acceleration sensor circuit (comparison malfunction) | ||
| Yaw rate sensor circuit (comparison malfunction) | ||
| Yaw rate and acceleration sensor circuit (internal malfunction) | ||
| Steering angle sensor circuit (output malfunction) | ||
| Steering angle sensor circuit (power source voltage malfunction) | ||
| Steering angle sensor circuit (internal malfunction) | ||
| Replace the ECM (for 1ZR-FAE). | ||
| Replace the ECM (for 2ZR-FAE). | ||
| Replace the ECM (for 1WW). | ||
| If the symptoms still occur even after the above suspected areas have been inspected and proved to be normal, replace the skid control ECU (Brake actuator assembly). | ||
| VSC sensor DTC check cannot be performed | Check again to see if DTCs are output. (If DTCs are output, perform diagnosis based on the DTCs that are output.) | |
| TC and CG terminal circuit | ||
| If the symptoms still occur even after the above suspected areas have been inspected and proved to be normal, replace the skid control ECU (Brake actuator assembly). | ||
| TRC OFF indicator (multi-information display) abnormal (Remains on) | TRC OFF indicator (multi-information display) circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| TRC OFF indicator (multi-information display) abnormal (Does not come on) | TRC OFF indicator (multi-information display) circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| VSC OFF indicator light abnormal (Remains on) | VSC OFF indicator light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| VSC OFF indicator light abnormal (Does not come on) | VSC OFF indicator light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| Slip indicator light abnormal (Remains on) | Slip indicator light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| Slip indicator light abnormal (Does not come on) | Slip indicator light circuit | |
| Skid control ECU (Brake actuator assembly) | ||
| Sensor check cannot be performed | TS and CG terminal circuit | |
| Skid control ECU (Brake actuator assembly) |