GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2006 🢒 Epica 🢒 DTC 🢒 DTC P1562 or P1563

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 provide an overview of each diagnostic category.

DTC Descriptors

DTC P1562: System Voltage Low

DTC P1563: System Voltage High

Circuit/System Description

The engine control module (ECM) uses the ignition 1 voltage circuit to monitor system voltage. Voltage that is out of range will cause damage to components and incorrect input readings.

Conditions for Running the DTC

P1562

    • The ignition is ON or the engine is operating.
    • DTC P1562 runs continuously once the above conditions are met.

P1563

    • The ignition is cycled from the ON position to the OFF position.
    • DTC P1563 runs continuously once the above conditions are met.

Conditions for Setting the DTC

P1562

The ECM detects a voltage below 7.9 volts or more than 26 volts on the ignition voltage circuit for more than 10 seconds.

P1563

The ECM detects a voltage of more than 7.9 volts on the ignition voltage circuit when the ignition is turned OFF for more than 1 second.

Action Taken When the DTC Sets

DTC P1562 is a Type C DTC.

DTC P1563 is a Type B DTC.

Conditions for Clearing the DTC

DTC P1562 is a Type C DTC.

DTC P1563 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

    •  Engine Control Module Connector End Views
    •  Engine Controls Connector End Views

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

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Circuit/System Verification
  1. Ignition ON, observe the scan tool DTC information parameter. Verify that DTCs P1610 or P1611 are not also set.
    2. ⇒If DTCs P1610 or P1611 are set, refer to DTC P1610 or P1611 for further diagnosis.
  2. Engine idling, observe the scan tool ignition 1 voltage parameter. The reading should be between 12-15 volts.
  3. If the vehicle passes the Circuit/System Verification test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.

Circuit/System Testing
  1. Engine idling, verify the scan tool ignition 1 voltage parameter is between 12-15 volts.
    2. ⇒If not within the specified range, refer to Charging System Test for further diagnosis.
  2. Test for 12-15 volts at the battery terminals .
    3. ⇒If less than the specified range, refer to Charging System Test for further diagnosis.
  3. Verify that the difference between the scan tool battery voltage and the scan tool ignition 1 voltage parameter is less than 1 volt.
    4. ⇒If greater than the specified range, test for an open/high resistance.
  4. If all circuits test OK, replace the ECM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for engine control module replacement, setup, and programming