4T80-E - Automatic Transaxle

DTC P2534

Diagnostic Instructions

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


DTC Descriptor
DTC P2534
- Ignition 1 Switch Circuit Low Voltage



Diagnostic Fault Information





Typical Scan Tool Data





Circuit/System Description

The transmission control module (TCM) samples the system voltage on the ignition 1 voltage circuit every 0.1 second. Lower than normal voltage may be inadequate to operate the transmission control solenoids properly. Improper solenoid operation may cause erratic transmission operation, which may result in internal transmission damage.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

The TCM detects an open or short to ground on the Ignition 1 voltage circuit.

Action Taken When the DTC Sets

DTC P2534 is a Type A DTC.

Conditions for Clearing the DTC

DTC P2534 is a Type A DTC.

Reference Information
Schematic Reference

Automatic Transmission Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and operation

Transmission General Description (Transmission General Description)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning)
Special Tools

J 35616 GM-Approved Terminal Test Kit

Circuit/System Verification

Ignition ON, observe the Ignition 1 Signal parameter with the scan tool. The Ignition 1 Signal parameter should read between 12.0-14.5 volts.

Circuit/System Testing

1. Measure the voltage at the battery terminals and compare it with the Ignition 1 Signal parameter on the scan tool. Verify that battery and Ignition 1 signal readings do not differ more than 1.0 volt.

• If greater than 1.0 volt, test the Ignition 1 and ground circuits of the TCM for high resistance. If the circuits test normal replace the TCM.

2. Go toCharging System Test (Charging System Test).


Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.

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