P2535

DTC P2535

Diagnostic Instructions

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

DTC Descriptor
DTC P2535
- Ignition 1 Switch Circuit High Voltage

Circuit Description

The Run/Crank relay is controlled by the body control module (BCM). The Run/Crank relay contacts are supplied a hot at all times from the fuse block underhood. The relay supplies power to several components when the vehicle is in the RUN or CRANK power mode. This signal is labeled Ignition 1. When the ignition switch is placed in the RUN or CRANK position, the BCM will receive a Run/Crank signal from the ignition switch and turn ON the Run/Crank relay. When the ignition switch is in the OFF position, the BCM will turn OFF the Run/Crank relay. The powertrain control module (PCM) compares the Run/Crank relay output signal with the BCM Class 2 serial data power mode message. If the ignition 1 voltage signal and the power mode message do not match for an allotted time, the PCM will disable the fuel injectors and DTC P2535 will set.


Conditions for Running the DTC

* The vehicle is in PARK or NEUTRAL.
* The ignition switch is OFF.

Conditions for Setting the DTC

The ignition 1 voltage signal is higher than normal.

Reference Information
Schematic Reference

Power Moding Schematics (Power Moding Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Power Mode Description and Operation (Power Mode Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information.

Circuit/System Testing

1. Ignition OFF, disconnect the Run/Crank relay.
2. Ignition ON, verify a test lamp does not illuminate between the Run/Crank voltage circuit terminal and ground.

• If the test lamp illuminates, test the ignition 1 voltage circuit for a short to voltage. If the circuit tests normal, replace the BCM

3. Reconnect the Run/Crank relay, and disconnect the harness connector of the ECM.
4. Verify a test lamp does not illuminate between the Run/Crank voltage circuit terminal and ground.

• If the test lamp illuminates, test the Run/Crank voltage circuit for a short to voltage. If the circuit tests normal, replace the Run/Crank relay.

5. If all circuits test normal, replace the ECM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for BCM, and ECM replacement, setup, and programming