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 Descriptor

DTC P0700: Transmission Control Module (TCM) Requested MIL Illumination

### Circuit/System Description

This DTC indicates the transmission control module (TCM) has set an emission related transmission DTC. The engine control module (ECM) receives the TCM information over the serial data circuit. The ECM illuminates the malfunction indicator lamp (MIL) when the TCM sends a message over the serial data circuit requesting MIL illumination. The DTC information for the ECM will only display DTC P0700, but the freeze frame/failure records data may display the transmission DTC that set.

### Conditions for Running the DTC

• | The ignition is ON.

• | DTC P0700 runs continuously.

### Conditions for Setting the DTC

The TCM is requesting MIL illumination.

### Action Taken When the DTC Sets

DTC P0700 is a Type A DTC.

### Conditions for Clearing the DTC

DTC P0700 is a Type A DTC.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Description and Operation

Transmission Component and System Description

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

Note: Correct any Engine Controls DTCs before diagnosing TCM DTCs.

DTC P0700 is an informational DTC. If there are no Engine Controls DTCs, refer to Diagnostic Trouble Code (DTC) List - Vehicle for diagnosis of TCM DTCs.