Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
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
Circuit/System Description
The internal fault detection is handled inside the transmission control module (TCM). No external circuits are involved.
Conditions for Running the DTC
This diagnostic applies to internal microprocessor integrity conditions within the TCM. This diagnostic also addresses if the TCM is not programmed.
Conditions for Setting the DTC
The TCM detects an internal malfunction.
Action Taken When the DTC Sets
| • | DTCs P0601, P0602, P0603, P0604 and P062F are Type A DTCs. |
| • | The TCM commands maximum line pressure. |
| • | The TCM forces the torque converter clutch (TCC) OFF. |
| • | The TCM inhibits the TCC engagement. |
| • | The TCM freezes transmission adaptive functions. |
P0601, P0603, P0604, and P062F
The TCM commands a soft landing to 2nd gear.
P0602
The TCM commands an immediate landing to 2nd gear.
Conditions for Clearing the DTC
DTC P0601, P0602, P0603, P0604 and P062F are Type A DTCs.
Diagnostic Aids
DTC P0602 indicates the TCM is not programmed.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Description and operation
Transmission General Description
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
- Ignition ON, clear the DTC information with a scan tool. Observe the scan tool DTC information. Verify that DTC P0602 does not fail this ignition.
- Observe the DTC information with a scan tool. Verify that DTCs P0601, P0603, P0604, or P062F do not set this ignition cycle.
| ⇒ | If DTC P0602 failed this ignition, reprogram the TCM. If DTC P0602 resets, replace the TCM. |
| ⇒ | If any of the DTCs P0601, P0603, P0604, or P062F are set this ignition cycle, replace the TCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
Control Module References for TCM replacement, setup, and programming
