Diagnostic Instructions
DTC Descriptor
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. These DTCs are Type A DTCs.
Conditions for Running the DTC
The TCM runs the program to detect an internal fault when the engine is running. The only requirements are voltage and ground. This program runs even if the voltage is out of the valid operating range.
Conditions for Setting the DTC
The TCM has detected an internal malfunction.
Action Taken When the DTC Sets
• | DTCs P0601, P0602, P0603, P0604 are Type A DTCs. |
• | The TCM commands second gear. |
• | The TCM commands maximum line pressure. |
• | The TCM commands HSD1 and HSD2 OFF. |
• | The TCM forces the TCC OFF. |
• | The TCM inhibits the TCC solenoid. |
• | The TCM freezes transmission adaptive functions. |
P062F
• | DTC P062F is a Type A DTC. |
• | The TCM commands HSD1 OFF. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
Conditions for Clearing the DTC
DTCs 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
Component Connector End Views
Description and Operation
Transmission General Description
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Transmission Control Module Scan Tool Information
Circuit/System Verification
Verify that DTC P0602 is not set.
⇒ | If DTC P0602 is set, program the TCM. |
⇒ | If DTC P0602 is not set, replace the TCM |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the repair.
Control Module References
for TCM replacement, setup, and programming.