For 1990-2009 cars

### Circuit Description

This DTC indicates that an emission related transmission fault has occurred. The transmission control module (TCM) illluminates a service transmission lamp (STL) or flashes the Sport mode lamp (on second design) when a fault occurs on certain non-emissions related TCM systems. The TCM has no direct control of the malfunction indicator lamp (MIL), but if a transmission fault occurs that is emissions related, the MIL must illuminate. The TCM transmits a MIL request signal over the CAN bus to the ECM and the ECM will turn on the MIL. This allows the MIL to illuminate, even though the fault was detected by the TCM.

### Conditions for Running the DTC

Tested continuously

### Conditions for Setting the DTC

An emission related transmission DTC has been stored by the TCM.

### Action Taken When the DTC Sets

• | The ECM illuminates the malfunction indicator lamp (MIL) immediately after the request from the TCM is received.

• | The ECM records operating conditions at the time the TCM initiates the request. This information will store in the Freeze Frame.

### Conditions for Clearing the MIL/DTC

• | The ECM will turn the MIL off approximately 1 second after the request from the TCM is no longer received.

• | A History DTC clears after forty consecutive warm-up cycles if no failures report by this diagnostic or any other emission related diagnostic.

• | The ECM battery voltage is interrupted.

• | The scan tool clears the MIL/DTC.

#### DTC P1700 - MIL Requested By TCM

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System check? | -- | Go to Transmission Diagnosis in Transmission. | Go to Powertrain On Board Diagnostic (OBD) System Check