B1483

Anti-Lock Control

Pinpoint Test A: DTC B1483

Refer to Wiring Diagram Set 42, Vehicle Dynamic Systems for schematic and connector information Electrical Diagrams.

NOTE: The Brake Pedal Position (BPP) is also known as the stoplamp switch.

Normal Operation

When the brake pedal is pressed, the BPP (Brake Pedal Position) switch opens and interrupts a voltage signal that is sent to the PCM. When the PCM detects this interruption, it sends a message over the High Speed Controller Area Network (HS-CAN) indicating that the brake pedal has been pressed. The PCM uses the BPP (Brake Pedal Position) switch information for the speed control system. The ABS module receives the BPP (Brake Pedal Position) switch information from the PCM over the HS-CAN (High Speed Controller Area Network).

- DTC B1483 (Brake Pedal Input Open Circuit)- The ABS module compares the BPP (Brake Pedal Position) message against other inputs (brake pressure and wheel speed) and if the message does not match the other inputs and there are no DTCs present for those inputs, DTC B1483 is set.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- BPP (Brake Pedal Position) switch

- PCM

- ABS module

PINPOINT TEST A : DTC B1483

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

A1 CHECK FOR PCM DTCs

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: Self-Test- PCM KOEO (Key ON Engine OFF).

- Retrieve and record any PCM DTCs.

Are any DTCs present in the PCM?

Yes
REFER to Body Control Systems.

No
GO to A2.

A2 CHECK THE ABS MODULE DTCs

- Review the DTCs recorded during Inspection and Verification.

Are DTCs U0100 and/or U0401 also present?

Yes
DIAGNOSE U0100 and/or U0401 before diagnosing DTC B1483. REFER to the ABS Module DTC Chart. Antilock Brakes / Traction Control Systems

No
If DTC C1288 is present, GO to Pinpoint Test R. Pinpoint Test R: DTC C1288

If no other DTCs are present, GO to A3.

A3 CHECK THE ABS MODULE BRAKE ON/OFF (BOO_ABS) PID

- Enter the following diagnostic mode on the scan tool: DataLogger- ABS Module.

- Monitor the BOO_ABS PID while pressing and releasing the brake pedal.

Does the PID agree with the pedal position?

Yes
The system is operating correctly at this time. CLEAR the DTC. REPEAT the self-test.

No
GO to A4.

A4 CHECK THE PCM BRAKE ON/OFF (BOO1) PID

- Enter the following diagnostic mode on the scan tool: DataLogger- PCM.

- Monitor the BOO1 PID while pressing and releasing the brake pedal.

Does the PID agree with the pedal position?

Yes
REFER to Information Bus to diagnose the communication concern.

No
REFER to Fire Suppression System and diagnose the speed control deactivation switch.