To the top of the document
Orlando
   
GMDE Start Page Load static TOC Load dynamic TOC Help?

DTC P2537

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 P2537: Ignition Accessory Switch Circuit Low Voltage

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Short to Voltage

Signal Performance

Accessory Wake-up

P2537

P2537

--

--

Ground

--

P2537

--

--

Circuit/System Description

With ignition in the accessory position or ignition ON, the BCM supplies a 12 volt wake up signal on the Ignition Accessory/Run circuit. The transmission control module (TCM) continuously monitors the Accessory/Run circuit. This wake up signal allows the TCM to power up and start functioning.

Conditions for Running the DTC

Engine is running.

Conditions for Setting the DTC

The TCM does not detect 6 volts or greater on the accessory wake up circuit within 32 seconds following startup.

Action Taken When the DTC Sets

DTC P2537 is a Type C DTC.

Conditions for Clearing the DTC

DTC P2537 is a Type C DTC.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

    •  Component Connector End Views
    •  Inline Harness Connector End Views

Description and Operation

    •  Transmission Component and System Description
    •  Electronic Component Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

DT-48616-10 Adapter Harness

For equivalent regional tools, refer to Special Tools .

Circuit/System Verification
  1. Verify with a scan tool that there are no DTCs set in the BCM.
    2. [ARW-LISTFAIL]

  2. If DTCs are set in the BCM

    Refer to Diagnostic Trouble Code (DTC) List - Vehicle .

    3. [/ARW-LISTFAIL][ARW-LISTPASS]

  3. If DTCs are not set in the BCM

    4. [/ARW-LISTPASS]
  4. Ignition switch in the Accessory position, verify the scan tool BCM Accessory parameter displays Active.
    5. [ARW-LISTFAIL]

  5. If the Accessory parameter does not display Active

    Refer to Power Mode Mismatch .

    6. [/ARW-LISTFAIL][ARW-LISTPASS]

  6. If the Ignition Switch Accessory Signal parameter displays Active

    7. [/ARW-LISTPASS]
  7. Ignition switch in the Run position, verify the scan tool BCM Ignition Switch Accessory Signal parameter displays Active.
    8. [ARW-LISTFAIL]

  8. If the Ignition Switch Accessory Signal parameter does not display Active

    Refer to Power Mode Mismatch .

    9. [/ARW-LISTFAIL][ARW-LISTPASS]

  9. If the Ignition Switch Accessory Signal parameter displays Active

    10. [/ARW-LISTPASS]
  10. Ignition ON, clear the BCM and TCM of all DTCs.
  11. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.
  12. Engine running in park position for 1 minute. Verify DTC P2537 is not set in the TCM.
    13. [ARW-LISTFAIL]

  13. If DTC P2537 is set

    Refer to Circuit/System Testing below.

    14. [/ARW-LISTFAIL][ARW-LISTPASS]

  14. If DTC P2537 is not set

    15. [/ARW-LISTPASS]
  15. After performing the above steps, verify that the DTC does not reset by operating the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions you observe from the Freeze Frame/Failure Records data. If the vehicle passes the Circuit/System Verification procedure, then STOP. Do not perform the Circuit/System Testing or Component Testing as this may result in an unnecessary part replacement. Refer to Testing for Intermittent Conditions and Poor Connections .

Circuit/System Testing
  1. Ignition OFF, and all vehicle systems OFF, disconnect the X1 14-way harness connector at the transmission.
  2. Connect the DT-48616-10 harness to the vehicle wire harness X1 14-way transmission connector.
  3. Ignition ON, verify a test lamp illuminates between terminal 13 and ground at the transmission case.
    4. [ARW-LISTFAIL]

  4. If the test lamp does not illuminate and the circuit fuse is good

    5. [/ARW-LISTFAIL]
    3.1. Ignition OFF, and all vehicle systems OFF.
    3.2. Test for less than 2 Ω in the Accessory voltage circuit end to end.
    [ARW-LISTFAIL]

  5. If 2 Ω or greater, repair the open/high resistance in the circuit.

  6. If less than 2 Ω, replace the K9 body control module

    7. [/ARW-LISTFAIL][ARW-LISTFAIL]

  7. If the test lamp does not illuminate and the circuit fuse is open

    8. [/ARW-LISTFAIL]
    3.1. Ignition OFF.
    3.2. Test for infinite resistance between the ignition accessory circuit and ground.
    [ARW-LISTFAIL]

  8. If less than infinite resistance, repair the short to ground in the circuit.

  9. If infinite resistance, replace fuse and retest. If fuse opens again, refer to Testing for Intermittent Conditions and Poor Connections .

    10. [/ARW-LISTFAIL][ARW-LISTPASS]

  10. If the test lamp illuminates

    11. [/ARW-LISTPASS]
  11. Replace the Q8 control solenoid valve assembly

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    • Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection .
    • Refer to Control Module References for control solenoid valve assembly replacement, set-up, and programming.
    • Perform the Transmission Adaptive Values Learn following all transmission related repairs.
   


© Copyright Chevrolet. All rights reserved