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For 1990-2009 cars only

DTC P0562 ECM

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 P0562: System Voltage Low

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

IGN I

P0562

P0562

--

--

Ground

--

P0562

--

--

Circuit/System Description

The engine control module (ECM) monitors the system voltage to ensure that the voltage stays within the proper range. Damage to components, and incorrect data may occur when the voltage is out of range.

Conditions for Running the DTC

    • The vehicle speed is above 8 km/h (5 mph).
    • The system voltage is between 9.5-18 V.

Conditions for Setting the DTC

The ECM detects a system voltage below 10 V.

Action Taken When the DTC Sets

    • The instrument panel cluster (IPC) illuminates the charge indicator.
    • The driver information center (DIC) displays the SERVICE BATTERY CHARGING SYSTEM warning message.

Conditions for Clearing the DTC

DTC P0562 is a C type DTC.

Diagnostic Aids

    • A low voltage DTC in multiple modules indicates a concern in the charging system.
    • A low voltage value in multiple modules indicates a concern in the charging system.
    • Inspect the ECM ground connection, to verify that it is clean tight.

Reference Information

Schematic Reference

    •  Engine Controls Schematics for the 4.3L engine.
    •  Engine Controls Schematics for V8 gas engines.
    •  Engine Controls Schematics for the 6.6L engine.

Connector End View Reference

Component Connector End Views

Description and Operation

Charging System Description and Operation

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 Verification

  1. Engine running measure and record the voltage at the battery terminals. Verify that the battery voltage is 12.6-15.5 V.
  2. If the battery voltage is not within the specified range, refer to Charging System Test.
  3. Observe the scan tool ECM Ignition 1 Signal parameter. The reading should be between 12.6 and 15.0 V.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connectors at the ECM.
  2. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 Ω between the ground circuit terminals listed below and ground:
  3. • 4.3L terminal 73 X2.
    • V8 gas engines terminal 73 X1.
    • 6.6L terminals 2-4 and 6 X2.
    If greater than the specified range, test the ground circuit(s) for an open/high resistance.
  4. Verify that a test lamp illuminates between the B+ circuit terminals listed below and ground.
  5. • 4.3L terminals 19 and 73 X1.
    • V8 gas engines X1 terminals 19 and 47 X1.
    • 6.6L terminal 77 X1 and terminals 1-3-5 X2.
    If the test lamp does not illuminate , test the Ignition circuits for a short to ground or an open/high resistance.
  6. If all circuits test normal, replace the ECM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming.

DTC P0562 FSCM

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 P0562: System Voltage Low - FPCM

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

B+

P0562

P0562

--

--

Ground

--

P0562

--

--

Circuit/System Description

The fuel pump control module (FPCM) monitors the system voltage to ensure that the voltage stays within the proper range. Damage to components, and incorrect data may occur when the voltage is out of range.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

The FPCM detects that the battery voltage is less than 9 V.

Action Taken When the DTC Sets

DTC P0562 is a type C DTC.

Conditions for Clearing the DTC

DTC P0562 is a type C DTC.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Charging System Description and Operation

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

  1. Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 V.
  2. If not within the specified range, refer to Charging System Test.
  3. Ignition OFF, disconnect the harness connectors at the FPCM.
  4. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 Ω between the ground circuit terminal 1 and ground.
  5. If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Verify that a test lamp illuminates between the B+ circuit terminal 32 and ground.
  7. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  8. If all circuits test normal, replace the FPCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for FPCM replacement, setup, and programming.