Engine Electrical
DTC P0562
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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 - ECM
Diagnostic Fault Information
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 if the voltage is out of range. If the ECM detects that the system voltage is too low, then DTC P0562 sets.
Conditions for Running the DTC
* The vehicle speed is above 8 km/h (5 mph).
* The system voltage is between 9.5-18 volts.
Conditions for Setting the DTC
The ECM detects a system voltage below 10 volts for 5 seconds.
Action Taken When the DTC Sets
DTC P0562 is a C type DTC.
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.
* Inspect the ECM ground connection, to verify that it is clean and tight.
Circuit/System Verification
1. Measure and record the voltage at the battery terminals with the engine OFF, and again with the engine running. Verify that the battery voltage is 11-16 volts with the engine off and with the engine running.
• If the battery voltage is not within the specified range, refer to Charging System Test (Acadia or Enclave) Charging System Test (OUTLOOK). Charging System Test Charging System Test
2. Ignition ON. Observe the Ignition 1 Signal parameter in the ECM scan tool data list. Verify that the scan tool displays a value that is within 2 volts of the battery voltage recorded in step 1.
• If the scan tool parameter is not within the specified range, refer to Circuit/System Testing.
3. Refer to Diagnostic Aids.
Circuit/System Testing
1. Ignition OFF, disconnect the X2 harness connector of the ECM. Verify that there is less than 1.0 ohm between the ground circuit X2 terminal 73 and the negative battery terminal.
• If greater than the specified value, test the ground circuit for an open/high resistance.
2. Ignition ON, test for 11-14 volts between the ECM battery positive voltage circuits X2 terminals 13 and 18, and the ground circuit X2 terminal 73.
• If not within the specified range, test the battery positive voltage circuits for a short to ground or an open/high resistance.
3. If all circuits test normal, test or replace the ECM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests