Transmission Diagnosis

DTC P0601

Circuit Description
A normal function of the transmission control module (TCM) is to perform an internal test that verifies the integrity of the read-only memory (ROM) memory allocation. This diagnostic detects faults in the allocation of flash memory that contains the program and calibration by comparing a calculated checksum with a stored checksum. When the TCM detects that the calculated checksum is different from the stored checksum, DTC P0601 sets. DTC P0601 is a type A DTC.

DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0601 Transmission Control Module (TCM) Read Only Memory (ROM)

Conditions for Running The DTC
The ignition is ON.

Conditions for Setting The DTC
The TCM electrically-erasable programmable read-only memory (EEPROM) checksums do not match.

Action Taken When the DTC Sets
^ The TCM requests the engine control module (ECM) to illuminate the malfunction indicator lamp (MIL).
^ The TCM commands maximum line pressure.
^ The TCM freezes transmission adaptive functions.
^ The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records.
^ The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Records.
^ The TCM stores DTC P0601 in TCM history.

Conditions for Clearing the MIL/DTC





^ The ECM turns OFF the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request.
^ A scan tool can clear the MIL/DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.
^ The TCM cancels the default actions when the ignition switch is OFF long enough in order to power down the TCM.