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 LowDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Ignition 1 Signal | P0562 | P0562 | -- | -- |
Ground Circuit | 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 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.
Reference Information
Schematic Reference
| • | Engine Controls Schematics for the 6.6L engine. |
| • | Engine Controls Schematics for the 7.2L engine. |
| • | Engine Controls Schematics for the 7.8L engine. |
| • | Engine Controls Schematics for the 8.1L engine. |
Connector End View Reference
Description and Operation
Charging System Description and Operation
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Engine running, observe the scan tool ECM Ignition 1 Signal parameter. The Ignition 1 Signal parameter should read 10.5 volts or greater.
Circuit/System Testing
- Verify that DTC P0562 is set as current.
- Engine running, measure the voltage at the battery terminals and compare it with the Ignition 1 Signal parameter. The battery and Ignition 1 signal readings do not differ more than 2 volts.
- If the circuits test normal, replace the ECM.
| ⇒ | If the DTC is history refer to Charging System Test |
| ⇒ | If greater than the specified value, test the Ignition 1 circuits and ground circuits for an open/high resistance. |
| • | Ignition 1 signal 6.6L X1 terminal 76 X2 terminals 1-3-5-21 |
| • | Ground circuits 6.6L X2 terminals 2-4-6 |
| • | Ignition 1 signal 7.2L X1 terminal 70 |
| • | Ground circuits 7.2L X1 terminals 63-65-67-69 |
| • | Ignition 1 signal 7.8L X1 terminals 23-49-50-73 |
| • | Ground circuits 7.8L X1 terminals 2-3-4-5-26-27 |
| • | Ignition 1 signal 8.1L X1 terminal 19 |
| • | Ground circuits 8.1L X1 terminals 1- 24-27-40 X2 terminals 1-40 |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for ECM replacement, setup, and programming.
