DTC C137B-A2: Brake System Control Module "A" System Voltage System Voltage Low [11/2023 - ]: Description
If a malfunction is detected in the power supply circuit, the skid control ECU (brake actuator assembly) stores this DTC and the fail-safe function prohibits operation of ABS, brake assist, etc.
This DTC is stored when the +BS terminal voltage meets one of the DTC detection conditions due to a malfunction in the power supply or charging circuit such as the auxiliary battery or alternator circuit, etc.
The DTC is cleared when the +BS terminal voltage returns to normal.
| DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
| C137B-A2 |
Brake System Control Module "A" System Voltage System Voltage Low |
Any of the following is detected:
- When the +BS terminal voltage is below 9.5 V, the power source voltage for all speed sensors is continuously low for 60 seconds or more.
- After the +BS terminal voltage is below 9.5 V continuously for 3 seconds or more, the +BS terminal voltage is below 9.5 V continuously for 7 seconds or more at a vehicle speed exceeding 3 km/h (2 mph).
- When the +BS terminal voltage is 9.5 V or higher and the vehicle speed exceeds 15 km/h (9 mph), the IG1 terminal voltage is 10 V or less continuously for 60 seconds or more.
- When the +BS terminal voltage is below 9.5 V and the solenoid relay is ON, the relay contact is OFF continuously for 1.22 seconds or more.
- When the +BS terminal voltage is below 9.5 V, motor fail-safe relay overcurrent continues for 1.05 seconds or more.
|
- Wire harness and connector
- Skid control ECU (brake actuator assembly)
- Backup boost converter circuit*
|
- *: w/ Stop and Start System