DTC C1252: Brake Booster Pump Motor on Time Abnormally Long; DTC C1253: Pump Motor Relay [09/2018 - ]: Description
The skid control ECU assembly detects decreases in the accumulator pressure according to the data from the accumulator pressure sensor, and then starts and stops the pump motor by operating the ABS motor relay.
The skid control ECU assembly usually drives the ABS motor relay 1 for electronically controlled brake system control, and the ABS motor relay 2 for ABS control. If either of them is malfunctioning, the other will substitute.
| DTC No. |
Detection Item |
INF Code |
DTC Detection Condition |
Trouble Area |
Note |
| C1252 |
Brake Booster Pump Motor on Time Abnormally Long |
130 |
ABS motor relay is on for at least 3 minutes. |
- Short in pump motor circuit or pump motor monitor circuit
- ABS motor relay stuck
- Accumulator pressure sensor malfunction in brake actuator assembly
- Brake fluid leaks
- Brake booster pump assembly is deteriorated
|
- |
| C1253 |
Pump Motor Relay |
134
138
140 |
- INF Code: 134
- MTT input is less than 3.5 V for at least 1 second or more when linear solenoid power source voltage 1 is 9.5 V or more, either of +BI1 or +BI2 voltage is 7 V or more, and ABS motor relay 1 is on.
- INF Code: 138
- MTT input is less than 3.5 V for at least 1 second or more when linear solenoid power source voltage 2 is 9.5 V or more, either of +BI1 or +BI2 voltage is 7 V or more, and ABS motor relay 2 is on.
- INF Code: 140
- MTT input is 3.5 V or more for at least 2 seconds when ABS motor relay 1 and 2 are off.
|
- INF Code: 134
- Improperly connected connector, deformation or corrosion of terminals
- Open in ABS motor relay 1 internal circuit
- Open or short in ABS motor relay 1 circuit
- Open in pump motor circuit or pump motor monitor circuit
- INF Code: 138
- Improperly connected connector, deformation or corrosion of terminals
- Open in ABS motor relay 2 internal circuit
- Open or short in ABS motor relay 1 circuit
- Open in pump motor circuit or pump motor monitor circuit
- INF Code: 140
- Short in ABS motor relay 1 circuit and ABS motor relay 2 circuit
- Short in pump motor circuit or pump motor monitor circuit
|
- |