For 1990-2009 cars

### 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 Descriptors

DTC P0562: System Voltage Low
DTC P0563: System Voltage High

### Circuit/System Description

The transmission control module (TCM) continuously monitors the Battery Positive Voltage. Improper voltage may cause component damage or 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

• | No Engine Speed Circuit Malfunction, P0727

• | No Lost Communications with the ECM, U0100

• | No CAN Bus Reset Counter Overrun, U2104

• | Engine speed is 1200 RPM or greater

• | Not in Emergency Mode

### Conditions for Setting the DTC

#### P0562

The TCM detects that battery voltage is less than 8.68 volts for 20 seconds.

#### P0563

The TCM detects that battery voltage is greater than 18.0 volts for 20 seconds.

### Action Taken When the DTC Sets

• | DTCs P0562 and P0563 are Type C DTCs.

• | The TCM inhibits Adaptive Control.

• | The transmission will operate in 5th gear in D or M range, 2nd gear in L range.

### Conditions for Clearing the DTC

DTCs P0562 and P0563 are Type C DTCs.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

• | Electrical Center Identification Views

• | Component Connector End Views

• | Splice Pack Connector End Views

• | Inline Harness 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

• | Diagnostic Trouble Code (DTC) List - Vehicle

#### Scan Tool Reference

Control Module References for scan information.

### Circuit/System Verification

Engine running, verify the transmission control module (TCM) scan tool battery voltage parameter is between 8.68-18.0 volts.

⇒ | If not within the specified range, refer to Charging System Test before performing Circuit/System Testing.

### Circuit/System Testing

You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, disconnect the C1 harness connector at the transmission control module (TCM).
2. Test for less than 1.0 ohm between ground circuit terminal 9 and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.

⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, replace the TCM.

⇒ | If all circuits test normal, replace the TCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.