4L60-E/4L65-E/4L70-E - Automatic Transmission

DTC P0601, P0602, P0603, P0604, or P062F

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 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.


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


P0601, P0604
* DTCs P0601, P0604 are Type A DTCs.
* The TCM commands soft landing to second gear.
* The TCM commands maximum line pressure.
* The TCM forces the TCC OFF.
* The TCM freezes transmission adaptive functions.



P0602, P0603, P062F
* DTCs P0602, P0603, P062F is a Type A DTCs.
* The TCM commands immediate landing to second gear.
* The TCM commands maximum line pressure.
* The TCM forces the TCC OFF.
* 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 (4.2L) (Electrical Diagrams)Automatic Transmission Controls Schematics (5.3L/6.0L) (Electrical Diagrams)
Connector End View Reference

Component Connector End Views
Description and Operation

Transmission General Information (Transmission General Information)
Electrical Information Reference

* Circuit Testing
* Connector Repairs
* Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs

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.