6L80-E Automatic Transmission

DTC P0562 or P0563

DTC Descriptor
This diagnostic procedure supports the following DTCs:
^ DTC P0562 System Voltage High
^ DTC P0563 System Voltage Low

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview

Circuit/System Description
The transmission control module (TCM) continuously monitors the system voltage on the Ignition 1 voltage circuits. Lower than normal voltage may be inadequate to operate the transmission control solenoids properly. Improper solenoid operation may cause erratic transmission operation, which may result in internal damage.

Conditions for Running the DTC

DTC P0562
^ Ignition voltage has been greater than 12 volts for 1 second this ignition cycle.
^ Engine speed is 1200 RPM or greater.

DTC P0563
Ignition voltage has been greater than 12 volts for 1 second this ignition cycle.

Conditions for Setting the DTC

DTC P0562
The TCM detects system voltage is 11.0 volts or less for 10 seconds.

DTC P0563
The TCM detects system voltage is 18 volts or greater for 10 seconds.

Action Taken When the DTC Sets
DTCs P0562 and P0563 are Type C DTCs.

Conditions for Clearing the DTC
DTCs P0562 and P0563 are Type C DTCs.

Diagnostic Aids
^ Observe the driver information center (DIC) messaging that would indicate the electrical system requires service.
^ Inspect for the following conditions:
- Loose or damaged terminals at the generator
- Loose or worn generator drive belt

Reference Information

Schematic Reference

Connector End View Reference
^ Automatic Transmission Inline 16-Way Connector End View
^ Automatic Transmission Internal Connector End Views

Scan Tool Reference
^ Scan Tool Output Controls
^ Scan Tool Data List
^ Scan Tool Data Definitions

DTC Type Reference
^ Diagnostic Trouble Code (DTC) Type Definitions
^ Diagnostic Trouble Code (DTC) List/Type

Electrical Information Reference
^ Circuit Testing
^ Connector Repairs
^ Testing for Intermittent Conditions and Poor Connections
^ Wiring Repairs

Circuit/System Verification
Engine ON, measure and record the battery voltage with a DMM. The battery voltage should be between 12.5 - 14.5 volts. If the voltage is not within the specified value, or the Charge Indicator light is ON, go to Charging System Test. Charging System Test

Circuit/System Testing
Engine ON, the scan tool Ignition Voltage parameter should display between 12.5 - 14.5 volts. If the voltage is not within the specified value, test the Ignition Voltage circuit for an Open circuit or Short to Ground.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests