Workshop Manuals Factory service & repair Vauxhall
Vauxhall Astra J05 · Body Systems
05 · Body & interior

DTC P0504, P0571, or P0703

Make
Vauxhall
Model
Astra J
Section
Lighting › Other Information › DTC P0504, P0571, or P0703
Body SystemsDTC P0504, P0571, or P0703

DTC P0504, P0571, or P0703

Diagnostic Instructions

•  Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
•  Review Strategy Based Diagnosis for an overview of the diagnostic approach.
•  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0504: Brake Switch Circuits 1-2 Not Plausible
DTC P0571: Brake Switch Circuit 1
DTC P0703: Brake Switch Circuit 2

Circuit/System Description

The body control module (BCM) monitors the brake pedal position sensor. When the brake pedal is applied, the BCM detects a predetermined voltage signal. The BCM sends a serial data message to the engine control module (ECM) indicating the status of the stop lamps.

Conditions for Running the DTC

•  The engine is running.
•  Battery voltage must be between 9-16 V.

Conditions for Setting the DTC

The ECM receives an invalid brake pedal status serial data message from the BCM.

Action Taken When the DTC Sets

P0504

•  The cruise control system is disabled.
•  The Stop/Start system is disabled.

P0571 or P0703

•  The SVS will illuminate.
•  The cruise control system is disabled.
•  The Stop/Start system is disabled.

Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists.

Reference Information


Schematic Reference

Cruise Control Schematics


Connector End View Reference

Component Connector End Views


Description and Operation

Cruise Control Description and Operation


Electrical Information Reference


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, verify that DTC C0277 is not present in the BCM.
⇒ If DTC C0277 is present, refer to DTC C0277 or C0890 .
2. Verify that DTC P0572 or P0573 is not present in the ECM.
⇒ If DTC P0572 or P0573 is present, refer to DTC P0572 or P0573 .
3. Observe the stop lamps while applying and releasing the brake pedal. Verify the stop lamps operate properly.
⇒ If the stop lamps do not operate properly, refer to Stop Lamps Malfunction .
4. Observe the ECM scan tool Brake Pedal Switch parameter. The reading should change when the brake pedal is pushed or released.
⇒ If the not the specified value, refer to Circuit/System Testing.

Circuit/System Testing

1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module.
2. Connect a test lamp between the signal circuit harness connector terminal listed below and ground:
  •  25 (LDD/LDE/LLU)
  •  38 (LBS/LSF)
  •  33 (LUJ)
3. Ignition ON, verify the test lamp turns ON and OFF when pressing and releasing the brake pedal.
⇒ If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.
⇒ If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.
4. If all circuits test normal, replace the K20 Engine Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM or ECM replacement, programming and setup

Parts & tools for this job For Vauxhall Astra

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