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Home >> Ford >> 2021 >> Edge ST-Line, 4WD >> Repair and Diagnosis (Single Page) >> External Pages >> Different car >> Section 496 (Abs Guided Routine) >> Pinpoint Tests >> Pinpoint Tests CT: ABS Module DTC C1A99 - Pressure Sensor >> Normal Operation and Fault Conditions
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Normal Operation and Fault Conditions

WARNING: This page is about a different car, the 2020 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.

The ABS module uses a pressure sensor located inside the HCU to monitor the integrity of the hydraulic system. When the brake pedal is pressed, the ABS module compares the value of the brake fluid line pressure sensor to the BOO switch input from the PCM over the HS-CAN. If the brake fluid pressure sensor value is not comparable to the BOO switch input, the ABS module sets one or more DTCs.

PPT CT ABS MODULE DTC FAULT TRIGGER CONDITIONS

DTC Description Fault Trigger Conditions
C1A99:01 Pressure Sensor: General Electrical Failure This DTC indicates the brake fluid line hydraulic pressure sensor signal circuit located inside the HCU has failed.
C1A99:28 Pressure Sensor: Signal Bias Level Out of Range/Zero Adjustment Failure This DTC indicates the brake fluid line hydraulic pressure sensor located inside the HCU has failed.