DTC C1391: Abnormal Leak in Accumulator [10/2018 - ]: Description
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This DTC is stored if internal or external brake fluid leaks are detected due to improper sealing in the brake actuator (brake booster with master cylinder assembly) or brake booster pump assembly. Internal leaks are suspected if the pump motor operates frequently without braking.
| DTC No. | Detection Item | INF Code | DTC Detection Condition | Trouble Area | MIL | Note |
|---|---|---|---|---|---|---|
| C1391 | Abnormal Leak in Accumulator | 351 | Either of the following is detected:
|
|
Does not come on | Electronically controlled brake system DTC |
DTC DETECTION CONDITIONS: C1391 INF CODE: 351
| Vehicle Condition | |||
|---|---|---|---|
| Pattern 1 | Pattern 2 | ||
| Diagnosis Condition | Brake pedal not depressed and pump motor operating. | ◦ | - |
| Brake pedal not depressed and pump motor not operating. | - | ◦ | |
| Malfunction Status | The accumulator pressure sensor value does not increase a certain number of times. | ◦ | - |
| The accumulator pressure sensor decrease rate exceeds a certain threshold a certain number of times. | - | ◦ | |
| Detection Time | - | - | |
| Number of Trips | 1 trip | 1 trip | |
HINT:
DTC will be output when conditions for either of the patterns in the table above are met.