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For 1990-2009 cars only

Circuit Description

This diagnostic trouble code (DTC) indicates that an emissions related transmission fault has occurred. The transmission control module (TCM) flashes the sport mode lamp 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 control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

DTC P1700 TCM Requested MIL Illumination

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check-Engine Controls?

Go to Powertrain On Board Diagnostic (OBD) System Check - Automatic Transmission in Automatic Transmission - 4L30-E

Go to Diagnostic System Check - Engine Controls