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 diagnostic trouble code (DTC) indicates that an emission related transmission DTC set in the transmission control module (TCM). The engine control module (ECM) receives the TCM information over the serial data circuit. The ECM turns ON 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 will display the transmission DTC that set.

### Conditions for Running the DTC

• | The ignition is ON or the engine is operating.

• | DTC P0700 runs continuously.

### Conditions for Setting the DTC

The ECM receives a serial data message, from the TCM, then a 5 second delay for MIL ON.

### 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

#### 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.

1. 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.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.