GM Service Manual Online
For 1990-2009 cars only

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 Descriptor

DTC P2534: Ignition 1 Switch Circuit Low Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open or High Resistance

Short to Voltage

Signal Performance

IGN Voltage

P2534

P2534

--

--

Circuit/System Description

The fuel pump flow control module (FPCM) monitors the ignition voltage circuit in order to determine if the voltage is within the normal operating range.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

The FPCM detects that the IGN voltage is less than 6.0 volts.

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

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Fuel System 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

Circuit/System Testing

Important: 

  1. Verify that DTC P0562 is not set.
  2. If DTC P0562 is set, refer to DTC P0562.
  3. Ignition OFF, disconnect the harness connector of the FPCM.
  4. Ignition ON, test for greater than 11 volts between the IGN voltage circuit terminal 15 and ground.
  5. If less than the specified voltage, test the IGN voltage circuit for a short to ground or an open/high resistance. If the circuit test normal and the ECM - IGN fuse 58 is open, test the voltage circuit for a short to ground. If the circuit tests normal, test or replace the Run/Crank relay.
  6. If all circuits test normal, replace the FPCM.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the Run/Crank relay.
  2. Test for 60-180 ohms between terminals 85 and 86.
  3. If the resistance is not within the specified range, replace the relay.
  4. Test for infinite resistance between the following terminals:
  5. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    If less than infinite resistance, replace the Run/Crank relay.
  6. Install a 20-amp fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2.0 ohms between terminals 30 and 87.
  7. If greater than 2.0 ohms, replace the Run/Crank relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Powertrain Relay Diagnosis
    •  Control Module References for FPCM replacement, setup, and programming