Circuit Description
The internal fault detection is handled inside the transmission control module (TCM). No external circuits are involved. These DTCs are type A DTCs.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC P0601 Transmission Control Module (TCM) Read Only Memory (ROM) |
| • | DTC P0602 Transmission Control Module (TCM) Not Programmed |
| • | DTC P0603 Transmission Control Module (TCM) Long Term Memory Reset |
| • | DTC P0604 Transmission Control Module (TCM) Random Access Memory (RAM) |
| • | DTC P062F Transmission Control Module (TCM) Long Term Memory Performance |
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The TCM has detected an internal malfunction.
Action Taken When the DTC Sets
| • | The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL). |
| • | The TCM commands second gear. |
| • | The TCM commands maximum line pressure. |
| • | The TCM inhibits torque converter clutch (TCC). |
| • | 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, P0602, P0603, P0604 or P062F in TCM history. |
Conditions for Clearing the 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 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 DTC default actions when the ignition is OFF long enough in order to power down the TCM. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
Is DTC P0602 set? | Go to Step 3 | Go to Step 4 | |
3 | Program the TCM. Refer to Control Module References for replacement, setup, and programming. Does DTC P0602 reset? | Go to Step 4 | Go to Step 5 |
4 | Replace the TCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 5 | -- |
5 | Perform the following in order to verify the repair:
Has the test run and passed? | Go to Step 6 | Go to Step 2 |
6 | With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | System OK |
