DTC C1288, C1290, C1440, C1730, C1954

BHE040243000W28

DTC

C1288, C1290, C1440, C1730, C1954

Brake fluid pressure sensor

DETECTION CONDITION

• C1288
– The pressure from the brake fluid pressure sensor when the system starts up is not within specification.
• C1290
– The pressure from the brake fluid pressure sensor when not braking exceeds specification.
• C1440
– The difference between the estimated brake fluid pressure response calculated by each sensor and the brake fluid pressure response from the brake fluid pressure sensor is not within specification.
• C1730
– The voltage to the brake fluid pressure sensor is not within specification.
• C1954
– The output voltage from the brake fluid pressure sensor is not within specification.

POSSIBLE CAUSE

• Open or short circuit in the wiring harness between DSC HU/CM terminal B and brake fluid pressure sensor terminal B
• Open or short circuit in the wiring harness between DSC HU/CM terminal C and brake fluid pressure sensor terminal C
• Open circuit in the wiring harness between DSC HU/CM terminal E and brake fluid pressure sensor terminal A
• Malfunction in the brake fluid pressure sensor
• Poor connection at connectors (female terminal)

Diagnostic procedure

STEP

INSPECTION

ACTION

1

INSPECT BRAKE FLUID PRESSURE SENSOR POWER SUPPLY FOR OPEN CIRCUIT

• Turn the ignition switch to the ON position (engine off).
• Measure the voltage between brake fluid pressure sensor terminal C (harness-side) and ground.
• Is the voltage 4.75-5.25 V?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit between brake fluid pressure sensor terminal C and DSC HU/CM terminal C, then go to Step 6.
2

INSPECT BRAKE FLUID PRESSURE SENSOR GROUND FOR OPEN CIRCUIT

• Turn the ignition switch off.
• Disconnect DSC HU/CM and brake fluid pressure sensor connectors.
• Inspect for continuity between DSC HU/CM terminal E (harness-side) and brake fluid pressure sensor terminal A (harness-side).
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit between DSC HU/CM terminal E and brake fluid pressure sensor terminal A, then go to Step 6.
3

INSPECT BRAKE FLUID PRESSURE SENSOR SIGNAL FOR OPEN CIRCUIT

• Inspect for continuity between DSC HU/CM terminal B (harness-side) and brake fluid pressure sensor terminal B (harness-side).
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit between DSC HU/CM terminal B and brake fluid pressure sensor terminal B, then go to Step 6.
4

INSPECT BRAKE FLUID PRESSURE SENSOR SIGNAL FOR SHORT TO GROUND

• Turn the ignition switch off.
• Inspect for continuity between DSC HU/CM terminal B (harness-side) and ground.
• Is there continuity?
Yes
Repair or replace the wiring harness for short to ground between DSC HU/CM terminal B and brake fluid pressure sensor terminal B, then go to Step 6.
No
Go to the next step.
5

INSPECT BRAKE FLUID PRESSURE SENSOR

• Inspect the brake fluid pressure sensor.
• Is the brake fluid pressure sensor normal?
Yes
Go to the next step.
No
Replace the DSC HU/CM, then go to the next step.
6

VERIFY DTC TROUBLESHOOTING COMPLETED

• Clear the DTC from the memory.
• Are the same DTCs present?
Yes
Replace the DSC HU/CM, then go to the next step.
No
Go to the next step.
7

VERIFY AFTER REPAIR PROCEDURE

• Are any other DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC Table.)
No
DTC troubleshooting completed.