Automatic Transmission - AF17-4
DTC P0601, P0603, or P0604
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0601
- Control Module Read Only Memory (ROM)
DTC P0603
- Transmission Control Module (TCM) Long Term Memory Reset
DTC P0604
- Control Module Random Access Memory (RAM)
Circuit/System Description
This diagnostic applies to internal microprocessor integrity conditions within the transmission control module (TCM) system.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
P0601
The TCM detects that the checksum calculation does not match the expected checksum.
P0603
The TCM detects an incorrect copy of non-volatile memory.
P0604
The TCM detects a random access memory (RAM) read/write error.
Action Taken When the DTC Sets
P0601 and P0604
* DTCs P0601 and P0604 are Type A DTCs.
* The transmission will operate in 4th gear in D range, Reverse in R range.
P0603
* DTC P0603 is a Type A DTC.
* The TCM uses default EEPROM values.
Conditions for Clearing the DTC
DTCs P0601, P0603 and P0604 are Type A DTCs.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Electronic Component Description (Electronic Component Description)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference
Control Module References (Programming and Relearning)
Circuit/System Verification
1. Observe the DTC information with a scan tool. Verify that DTCs P0601, P0603, P604 do not set this ignition cycle.
• If any of the DTCs P0601, P0603, or P604 are set this ignition cycle replace the TCM.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for TCM replacement, setup, and programming