Toyota Corolla Cross: Brake System Control Module "A" System Voltage Line Internal Electronic Failure (C117A49,C137BA2)
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 ABS, brake assist, regenerative braking, etc. operation.
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 DC/DC converter circuit, etc.
The DTC is cleared when the +BS terminal voltage returns to normal.
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
MIL |
DTC Output from |
Note |
|---|---|---|---|---|---|---|
|
C117A49 |
Brake System Control Module "A" System Voltage Line Internal Electronic Failure |
The vehicle speed is 15 km/h (9 mph) or more and the +BS terminal voltage is 9.6 V or more, the skid control ECU (brake actuator assembly) turns on more than one valve at the same time within a short period of time and the valve relay supply voltage drop exceeds the threshold.* |
|
Comes on |
Brake/EPB |
|
|
C137BA2 |
Brake System Control Module "A" System Voltage System Voltage Low |
Any of the following is detected:
|
|
Does not come on |
Brake/EPB |
Output ECU: Skid control ECU (brake actuator assembly) |
*: The skid control ECU (brake actuator assembly) monitors the resistance of the power source line at the +BS terminal. A malfunction is detected when an abnormality occurs in the +BS terminal wire harness or its connection and the skid control ECU (brake actuator assembly) determines that the wiring resistance at the +BS terminal exceeds the standard resistance.
MONITOR DESCRIPTION
When the vehicle speed is more than a certain value, the supply voltage of the skid control ECU (brake actuator assembly) is a certain value or more, the brake pedal is not depressed, and the resistance of the solenoid supply voltage line exceeds a certain value a certain number of times, the skid control ECU (brake actuator assembly) illuminates the MIL and stores this DTC.
MONITOR STRATEGY
|
Related DTCs |
C117A: Supply voltage line test |
|
Required Sensors/Components(Main) |
Skid control ECU (brake actuator assembly) |
|
Required Sensors/Components(Related) |
Speed sensor Skid control ECU (brake actuator assembly) Stop light switch assembly |
|
Frequency of Operation |
During initial checking |
|
Duration |
- |
|
MIL Operation |
Immediately |
|
Sequence of Operation |
None |
TYPICAL ENABLING CONDITIONS
|
Monitor runs whenever the following DTCs are not stored |
TMC's intellectual property |
|
Other conditions belong to TMC's intellectual property |
- |
TYPICAL MALFUNCTION THRESHOLDS
|
TMC's intellectual property |
- |
COMPONENT OPERATING RANGE
|
TMC's intellectual property |
- |
CONFIRMATION DRIVING PATTERN
NOTICE:
When performing the normal judgment procedure, make sure that the driver door is closed and is not opened at any time during the procedure.
HINT:
- After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
- When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
- Connect the GTS to the DLC3.
- Turn the ignition switch to ON and turn the GTS on.
- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
- Turn the ignition switch off.
- Turn the ignition switch to ON (READY) and turn the GTS on.
- Drive the vehicle at 15 km/h (9 mph) or more for 1 second. [*]
HINT:
[*]: Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
- Enter the following menus: Chassis / Brake/EPB* / Utility / All Readiness.
*: Electric Parking Brake System
- Check the DTC judgment result.
HINT:
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE, perform driving pattern again.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- Inspect the fuses for circuits related to this system before performing the following procedure.
- Before performing troubleshooting, make sure to confirm that the auxiliary
battery voltage is normal.
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PROCEDURE
|
1. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) |
|
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector. OK: The connector is securely connected. |
|
(b) Disconnect the A151 skid control ECU (brake actuator assembly) connector.
(c) Check both the connector case and the terminals for deformation and corrosion.
OK:
No deformation or corrosion.
(d) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A151-30 (+BS) - Body ground |
Always |
11 to 14 V |
| NG | .gif)
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
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|
2. |
CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) |
|
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector. OK: The connector is securely connected. |
|
(b) Disconnect the A151 skid control ECU (brake actuator assembly) connector.
(c) Check both the connector case and the terminals for deformation and corrosion.
OK:
No deformation or corrosion.
(d) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A151-1 (+BM) - Body ground |
Always |
11 to 14 V |
| OK |
|
REPLACE BRAKE ACTUATOR ASSEMBLY |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
