PRE-RELEASE
DTC P2544
| DTC P2544 |
| Diagnostic Instructions |
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Perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
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Review
Strategy Based Diagnosis
for an overview of the diagnostic approach.
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Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
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| DTC Descriptors |
DTC P2544
Transmission Torque Request Circuit
DTC P2544
Transmission Torque Request Signal Message Counter Incorrect
| Circuit/System Description |
To improve shift feel, the transmission control module (TCM) is constantly sending the engine control module (ECM) serial data messages with information regarding it's request for modifying engine speed or torque. The serial data messages are sent via two circuits that are part of a communications network known as the controller area network (CAN). The ECM sets DTC P2544 if it detects a deviation in the message structure which implies that the message may be corrupted.
An intermittent fault in the CAN circuits will cause the ECM to set DTC P2544.
| Conditions for Running the DTC |
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The engine run time is greater than 0.5 s.
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No other CAN errors are present.
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| Conditions for Setting the DTC |
The ECM detects that the engine speed and torque modification messages from the TCM are either corrupted or intermittently missing for greater than 4 s.
| Action Taken When the DTC Sets |
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DTC P2544 is a Type B DTC.
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The TCM commands maximum line pressure during shifts, which results in harsh shifts.
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The TCM freezes adaptive functions.
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| Conditions for Clearing the DTC |
DTC P2544 is a Type B DTC.
| Reference Information |
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
| Circuit/System Verification |
| 1. |
DTC P2544 is an informative error code. Diagnose all other DTCs from the ECM that were set before DTC P2544. Refer to
Diagnostic Trouble Code (DTC) List - Vehicle
.
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| 2. |
If no other DTCs are stored in the ECM, the diagnosis is performed by testing the CAN for intermittent circuit malfunctions. Go to
Scan Tool Not Communicating with High-Speed GMLAN Unit
.
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| Repair Instructions |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for TCM replacement, setup, and programming.
