DESCRIPTION If a
malfunction is detected in the power supply circuit, the skid control
ECU (brake booster with master cylinder assembly) power source voltage
drops, or there is insufficient voltage to operate the main relay, the
skid control ECU (brake booster with master cylinder assembly) will
store these DTCs. If the auxiliary battery voltage is temporarily low, these DTCs may be stored.
HINT: DTC C1256 (Accumulator Low Pressure) may also be memorized if there is a drop in power source voltage.
DTC No. | Detection Item |
INF Code | DTC Detection Condition |
Trouble Area | MIL |
Note | C1241 |
Low or High Power Supply Voltage |
101 102 103 551 552 554 |
- INF Code: 101
- Either of the following is detected when the BS terminal voltage is 9.1 V or less:
- The brake is not applied for 3 seconds or more.
- The brake is applied for 0.05 seconds or more.
- INF Code: 102
- Any of the following is detected when the ECU internal voltage is 6.92 V or less:
- The relay output voltage is less than 3.5 V for 0.05 seconds or more, when the main relay operation command is on.
- The stroke sensor value invalid for 0.2 seconds or more.
- The reaction force pressure sensor value invalid for 0.2 seconds or more.
- The servo pressure sensor power source voltage is 6.29 V or less, or 7.64 V or more for 0.06 seconds or more.
- The servo pressure sensor value invalid for 0.2 seconds or more.
- The reaction force pressure sensor power source voltage is 6.29 V or less, or 7.64 V or more for 0.06 seconds or more.
- INF Code: 103
- When the ECU internal voltage is 8.3 V or less, the accumulator pressure sensor value is invalid for 0.8 seconds or more.
- Either of the following is detected when the ECU internal voltage is 6.9 V or less:
- When the accumulator pressure sensor value is 15 MPa (153 kgf/cm2, 2176
psi) or less, the pump motor does not operate for 1 second or more.
- Both the motor relay 1 and 2 cannot be operated for 0.2 seconds or more.
- INF Code: 551
- Either of the following is detected when the BS voltage of the ABS unit is 9.1 V or less:
- The brake is not applied for 3 seconds or more.
- The brake is applied for 0.05 seconds or more.
- INF Code: 552
- The speed sensor power voltage is invalid for 60 seconds or more.
- INF Code: 554
- The voltage of IG1 or IG2 is 9.5 V or less for 10 seconds or more.
|
- Improperly connected connector, deformation or corrosion of terminals
- Auxiliary battery
- Hybrid control system (Charging circuit)
- Skid control ECU (brake booster with master cylinder assembly)
- Wire harness or connector
| Comes on |
- INF Code 101: SAE Code C14DE
- INF Code 102: SAE Code C1241 (Case 1 to 7)
- INF Code 103: SAE Code C1241 (Case 8 to 10)
- INF Code 551: SAE Code C14DB (Case 1 and 2)
- INF Code 552: SAE Code C1241 (Case 12)
- INF Code 554: SAE Code C1241 (Case 11)
- Electronically controlled brake system DTC
| MONITOR DESCRIPTION
- When the voltage at VM1, VM2, IG1, IG2 or BS drops due to a malfunction
in the auxiliary battery and hybrid control system (charging circuit),
the skid control ECU (brake booster with master cylinder assembly)
judges that there is a drop in the power supply and illuminates the MIL
and stores a DTC.
MONITOR STRATEGY
Related DTCs | C1241: Brake system voltage circuit low
C14DB: ABS solenoid power supply voltage circuit low C14DE: Main relay voltage circuit low |
Required Sensors/Components(Main) | Brake pedal stroke sensor assembly
Skid control ECU (brake booster with master cylinder assembly)
Brake booster pump assembly Brake actuator assembly Brake actuator (brake booster with master cylinder assembly) |
Required Sensors/Components(Related) | Speed sensor
Skid control ECU (brake booster with master cylinder assembly) |
Frequency of Operation | Continuous |
Duration | -: C1241 (Case 6), C1241 (Case 7) and C14DE (Case 1)
Within
1 second: C1241 (Case 1), C1241 (Case 2), C1241 (Case 3), C1241 (Case
4), C1241 (Case 5), C1241 (Case 8), C1241 (Case 9), C1241 (Case 10),
C14DB (Case 2) and C14DE (Case 3) 3 seconds: C14DB (Case 1) and C14DE (Case 2)
10 seconds: C1241 (Case 11) 60 seconds: C1241 (Case 12) |
MIL Operation | Immediately |
Sequence of Operation | None | TYPICAL ENABLING CONDITIONS C1241 (Case 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10)
Monitor runs whenever the following DTCs are not stored |
None | Vehicle electric power supply |
Stable state | C1241 (Case 11)
Monitor runs whenever the following DTCs are not stored |
None | Both of the following conditions are met |
- | IG1 | On |
Vehicle speed | Higher than 3 km/h (2 mph) | C1241 (Case 12)
Monitor runs whenever the following DTCs are not stored |
None | IG1 | On | C14DB
Monitor runs whenever the following DTCs are not stored |
C146E (ABS solenoid power supply relay circuit low) |
All of the following conditions are met | - |
Vehicle electric power supply | Stable state |
Command to ABS solenoid power supply relay |
On | ABS solenoid power supply relay |
On | ABS solenoid power supply relay fail (C146E) |
Not detected | C14DE
Monitor runs whenever the following DTCs are not stored |
C12FA (Main relay circuit low) | All of the following conditions are met |
- | Vehicle electric power supply |
Stable state | Command to main relay |
On | Main relay | On |
Main relay fail (C12FA) | Not detected | TYPICAL MALFUNCTION THRESHOLDS C1241 (Case 1)
Both of the following conditions are met | - |
Brake pedal stroke sensor assembly data |
Invalid | Brake system voltage 1 (VM1) |
6.92 V or less | C1241 (Case 2)
Both of the following conditions are met | - |
Reaction force pressure sensor data |
Invalid | Brake system voltage 1 (VM1) |
8.27 V or less | C1241 (Case 3)
Both of the following conditions are met | - |
Reaction force pressure sensor power supply |
Less than 6.29 V, or higher than 7.64 V | Brake system voltage 1 (VM1) |
8.27 V or less | C1241 (Case 4)
Both of the following conditions are met | - |
Servo pressure sensor data | Invalid |
Brake system voltage 1 (VM1) | 8.27 V or less | C1241 (Case 5)
Both of the following conditions are met | - |
Servo pressure sensor power supply | Less than 6.29 V, or higher than 7.64 V |
Brake system voltage 1 (VM1) | 8.27 V or less | C1241 (Case 6)
All of the following conditions are met | A, B and C |
A. Power switch | Off |
B. Either of the following conditions is met | - |
Main relay | Off and there is on experience |
ABS solenoid power supply relay | Off and there is on experience |
C. Brake system voltage 1 (VM1) | 6.92 V or less | C1241 (Case 7)
All of the following conditions are met | A, B, C and D |
A. Power switch | On (READY) |
B. Either of the following conditions is met | - |
Main relay | Off and there is on experience |
ABS solenoid power supply relay | Off and there is on experience |
C. Brake system voltage 1 (VM1) | 6.92 V or less |
D. IG1 voltage | 9.54 V or less | C1241 (Case 8)
Both of the following conditions are met | - |
Accumulator pressure data | Invalid |
Brake system voltage 2 (VM2) | 8.27 V or less | C1241 (Case 9)
All of the following conditions are met | - |
Serial communication with low side IC |
Valid | Pump motor operating from IC |
Enable | Accumulator pressure |
Less than 15.3 MPa (156 kgf/cm2, 2219 psi) (Pump motor on pressure) |
Brake system voltage 2 (VM2) | 6.92 V or less | C1241 (Case 10)
All of the following conditions are met | - |
Pump motor | Operating from IC |
Pump motor voltage | Less than 6 V |
Brake system voltage 2 (VM2) | 6.92 V or less | C1241 (Case 11)
One of the following conditions is met | A, B or C |
A. IG1 voltage | 9.54 V or less |
B. Both of the following conditions are met | - |
IG2 | On | IG2 voltage |
9.54 V or less | C. Brake system voltage 1 (VM1) |
7.54 V or less | C1241 (Case 12)
Both of the following conditions are met | - |
Brake system voltage 1 (VM1) | 7.54 V or less |
Speed sensor power supply voltage (all of wheels) | Less than 6.1 V | C14DB (Case 1)
Both of the following conditions are met | - |
Power supply for ABS solenoid | 9.13 V or less |
Brake control | Off | C14DB (Case 2)
Both of the following conditions are met | - |
Power supply for ABS solenoid | 9.13 V or less |
Brake control | On | C14DE (Case 1)
All of the following conditions are met | A, B and C |
A. Power supply for linear solenoid |
9.13 V or less | B. Either of the following conditions is met |
- | Linear solenoid (SLA) current drop signal |
On | Linear solenoid (SLR) current drop signal |
On | C. Brake control | On | C14DE (Case 2)
Both of the following conditions are met | - |
Power supply for linear solenoid | 9.13 V or less |
Brake control | Off | C14DE (Case 3)
Both of the following conditions are met | - |
Power supply for linear solenoid | 9.13 V or less |
Brake control | On | COMPONENT OPERATING RANGE C1241 (Case 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10)
Both of the following conditions are met |
- | Vehicle electric power supply |
Stable state | Power supply common pass condition |
Met | C1241 (Case 11)
All of the following conditions are met | - |
Control valve solenoid | non-drive |
IG1 voltage | Higher than 9.54 V |
IG2 voltage | Higher than 9.54 V |
Brake system voltage 1 (VM1) | Higher than 7.54 V | C1241 (Case 12)
Both of the following conditions are met |
- | IG1 |
On | Brake system voltage 1 (VM1) |
Higher than 7.54 V | C14DB
All of the following conditions are met |
- | Vehicle electric power supply |
Stable state | Command to ABS solenoid power supply relay |
On | ABS solenoid power supply relay |
On | ABS solenoid power supply relay fail (C146E) |
Not detected |
Power supply common pass condition |
Met | C14DE
All of the following conditions are met |
- | Vehicle electric power supply |
Stable state | Command to main relay |
On | Main relay |
On | Main relay fail (C12FA) |
Not detected |
Power supply common pass condition |
Met | CONFIRMATION DRIVING PATTERN
- Connect the Techstream to the DLC3.
- Turn the power switch on (IG).
- Turn the Techstream on.
- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
- Turn the power switch off.
- Turn the power switch on (READY).
- Turn the Techstream on.
- Drive the vehicle at 10 km/h (6 mph) or more for 60 seconds or more.
- Enter the following menus: Chassis / ABS/VSC/TRAC / Trouble Codes.
- Read the DTCs.
HINT:
- If a DTC is output, the system is malfunctioning.
- If a DTC is not output, perform the following procedure.
- If the DTCs are not output, perform a universal trip and check for permanent DTCs.
Click here
HINT:
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTCs are output, the system is normal.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- After replacing the skid control ECU (brake booster with master cylinder
assembly), perform linear solenoid valve offset learning, ABS holding
solenoid valve learning, yaw rate and acceleration sensor zero point
calibration and system information memorization after performing "Reset
Memory".
Click here
- Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE (a) Check the DTCs that are output.
Click here Chassis > ABS/VSC/TRAC > Trouble Codes
Result |
Proceed to | Only DTC C1241 is output. |
A | DTC C1311 is output with DTC C1241. |
B |
B |
| GO TO DTC (C1311) |
A |
| |
2. |
CHECK AUXILIARY BATTERY | (a) Select the Data List on the Techstream.
Click here Powertrain > Hybrid Control > Data List
Tester Display | Measurement Item |
Range | Normal Condition |
Diagnostic Note |
BATT Voltage | Auxiliary battery voltage
(Battery voltage sensor power source voltage) |
Min.: 0.00 V, Max.: 16.00 V |
11.00 to 15.00 V | BATT terminal | Powertrain > Hybrid Control > Data List
Tester Display | BATT Voltage |
(b) Check the Techstream display condition of the auxiliary battery voltage.
Result | Proceed to |
The auxiliary battery voltage is 11 to 15 V. |
A | The auxiliary battery voltage is below 11 V. |
B |
B |
| CHARGE OR REPLACE AUXILIARY BATTERY |
A |
| |
3. |
CHECK FREEZE FRAME DATA | (a) Check the INF code from the Freeze Frame Data stored when DTC (C1241) was stored.
Click here Chassis > ABS/VSC/TRAC > Trouble Codes
Result | Proceed to |
INF code 101 or 551 is output. |
A | INF code 102 or 552 is output. |
B | INF code 103 is output. |
C | INF code 554 is output. |
D |
B |
| GO TO STEP 5 |
C |
| GO TO STEP 6 |
D |
| GO TO STEP 7 |
A |
| |
4. |
CHECK HARNESS AND CONNECTOR (BS TERMINAL) |
(a) Turn the power switch off. |
|
*a | Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | | |
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK: The connector is securely connected. (c) Disconnect the A35 skid control ECU (brake booster with master cylinder assembly) connector.
(d) Check both the connector case and the terminals for deformation and corrosion.
OK: No deformation or corrosion. (e) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition |
Specified Condition |
A35-52 (BS) - Body ground |
Always | 11 to 14 V |
Result | Proceed to |
11 to 14 V. | A |
Below 11 V. | B |
A |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
B |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (BS CIRCUIT) |
5. |
CHECK HARNESS AND CONNECTOR (IG1, +BI1 AND BS TERMINAL) |
(a) Turn the power switch off. |
|
*a | Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | | |
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK: The connector is securely connected. (c) Disconnect the A35 skid control ECU (brake booster with master cylinder assembly) connector.
(d) Check both the connector case and the terminals for deformation and corrosion.
OK: No deformation or corrosion. (e) Turn the power switch on (IG).
(f) Measure the voltage according to the value(s) in the table below. Standard Voltage:
Tester Connection | Condition |
Specified Condition |
A35-15 (+BI1) - Body ground |
Power switch on (IG) |
11 to 14 V |
A35-52 (BS) - Body ground |
Power switch on (IG) |
11 to 14 V |
A35-23 (IG1) - Body ground |
Power switch on (IG) |
11 to 14 V |
Result | Proceed to |
11 to 14 V. | A |
Below 11 V. | B |
A |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
B |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1, +BI1 AND/OR BS CIRCUIT) |
6. |
CHECK HARNESS AND CONNECTOR (IG1, IG2, +BI1, +BI2 AND BS TERMINAL) |
(a) Turn the power switch off. |
|
*a | Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | | |
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK: The connector is securely connected. (c) Disconnect the A35 skid control ECU (brake booster with master cylinder assembly) connector.
(d) Check both the connector case and the terminals for deformation and corrosion.
OK: No deformation or corrosion. (e) Turn the power switch on (IG).
(f) Measure the voltage according to the value(s) in the table below. Standard Voltage:
Tester Connection | Condition |
Specified Condition |
A35-15 (+BI1) - Body ground |
Power switch on (IG) |
11 to 14 V |
A35-5 (+BI2) - Body ground |
Power switch on (IG) |
11 to 14 V |
A35-52 (BS) - Body ground |
Power switch on (IG) |
11 to 14 V |
A35-23 (IG1) - Body ground |
Power switch on (IG) |
11 to 14 V |
A35-9 (IG2) - Body ground |
Power switch on (IG) |
11 to 14 V |
Result | Proceed to |
11 to 14 V. | A |
Below 11 V. | B |
A |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
B |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1, IG2, +BI1, +BI2 AND/OR BS CIRCUIT) |
7. |
CHECK HARNESS AND CONNECTOR (IG1 AND IG2 TERMINAL) |
(a) Turn the power switch off. |
|
*a | Front view of wire harness connector
(to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | | |
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
OK: The connector is securely connected. (c) Disconnect the A35 skid control ECU (brake booster with master cylinder assembly) connector.
(d) Check both the connector case and the terminals for deformation and corrosion.
OK: No deformation or corrosion. (e) Turn the power switch on (IG).
(f) Measure the voltage according to the value(s) in the table below. Standard Voltage:
Tester Connection | Condition |
Specified Condition |
A35-23 (IG1) - Body ground |
Power switch on (IG) |
11 to 14 V |
A35-9 (IG2) - Body ground |
Power switch on (IG) |
11 to 14 V |
Result | Proceed to |
11 to 14 V. | A |
Below 11 V. | B |
A |
| REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY |
B |
| REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 AND/OR IG2 CIRCUIT) | |