Diesel Data: Automotive Repair

Pinpoint Test A: DTC B1483




Anti-Lock Control

Pinpoint Tests

Pinpoint Test A: DTC B1483

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

Normal Operation

Smart Junction Box (SJB) fuse 2 (15A) supplies fused battery voltage to the Brake Pedal Position (BPP) switch, along circuit SBP02 (YE/RD). With the brake pedal released, the switch is closed and voltage is supplied to the ABS module along circuit CCB08 (VT/WH). When the brake pedal is applied, the switch opens and the voltage supply is interrupted.

- DTC B1483 (Brake Pedal Input Open Circuit) - If during normal operation or the on-demand self test, the ABS module detects an open circuit on the BPP switch circuit, DTC B1483 will be set.

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- BPP switch
- ABS module


PINPOINT TEST A: DTC B1483

NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.

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A1 CHECK THE STOPLAMPS


- Apply the brake pedal while observing the stoplamps.
- Do the stoplamps illuminate?

Yes
GO to A2.

No
REFER to Exterior Lighting Testing and Inspection to continue diagnosis of the stoplamps.

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A2 CHECK THE VOLTAGE TO THE ABS MODULE


- Ignition OFF.
- Disconnect: ABS Module C155.
- Measure the voltage between ABS module C155-6, circuit CCB08 (VT/WH), harness side and ground with the brake pedal applied.




- Is the voltage greater than 10 volts?

Yes
GO to A6.

No
GO to A3.

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A3 CHECK THE BRAKE PEDAL INPUT CIRCUIT FOR AN OPEN


- Ignition OFF.
- Disconnect: BPP Switch C278.
- Measure the resistance between ABS module C155-6, CCB08 (VT/WH), harness side and BPP switch C278-4, circuit CCB08 (VT/WH), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to A4.

No
REPAIR circuit CCB08 (VT/WH). CLEAR the DTC. REPEAT the self-test.

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A4 ISOLATE THE BPP SWITCH


- Measure the resistance between BPP switch C278 pin-2 and pin-3, component side, while pressing and releasing the brake pedal.
- Is the resistance greater than 10,000 ohms with the pedal pressed and less than 5 ohms with the pedal released?

Yes
GO to A5.

No
INSTALL a new BPP switch. REFER to Stoplamp Switch in Exterior Lighting Service and Repair. CLEAR the DTC. REPEAT the self-test.

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A5 CHECK THE VOLTAGE TO THE BPP SWITCH


- Measure the voltage between BPP C278-1, circuit SBP02 (YE/RD), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to A6.

No
VERIFY SJB fuse 2 (15A) is OK. If OK, REPAIR circuit SBP02 (YE/RD). CLEAR the DTCs. REPEAT the self-test.

If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number

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A6 CHECK FOR CORRECT ABS MODULE OPERATION


- Check ABS module C155 for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: ABS Module C155.
- Make sure the connector seats correctly, then operate the system and verify the concern is still present.
- Is the concern still present?

Yes
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module Service and Repair. CLEAR the DTCs. REPEAT the self-test.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.

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