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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2008 🢒 Sierra - 2WD 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC P0700

Circuit Description

This diagnostic trouble code (DTC) indicates that a related transmission DTC set in the transmission control module (TCM). The engine control module (ECM) receives the TCM DTC 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.

DTC P0700 is a type A DTC.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0700 Transmission Control Module (TCM) Requested MIL Illumination

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

The ECM receives a serial data message from the TCM in order to illuminate the MIL.

Action Taken When the DTC Sets
    • The ECM illuminates the MIL when the diagnostic runs and fails.
    • The ECM 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 DTC
    • The ECM turns OFF the 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 scan tool can clear the code from TCM history. The TCM automatically clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without failure.

Step

Action

Yes

No

Schematic Reference: Automatic Transmission Controls Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

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2
  1. Install the scan tool.

    2. Important: 

       • Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records for reference. The Clear Info function will erase the data.
       • DTC P0700 is set by the ECM. DTC P0700 allows a technician to be alerted from the engine diagnostic side that the TCM is setting a DTC and is requesting the MIL.
       • If the TCM has DTCs set that are requesting MIL illumination, those DTCs must be diagnosed first. Refer to Obtaining Diagnostic Trouble Codes .

  2. Turn ON the ignition, with the engine OFF.

Does the scan tool display any DTCs other than DTC P0700?

Go to Diagnostic Trouble Code (DTC) List/Type

Go to Diagnostic System Check - Vehicle