For 1990-2009 cars

### 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

This is an internal fault detection of the control solenoid (w/body and TCM) valve assembly. This fault is handled inside the control solenoid (w/body and TCM) valve assembly and no external circuits are involved.

### Conditions for Running the DTC

• | The control solenoid (w/body and TCM) valve assembly runs the program to detect an internal fault when the key is ON or the engine is running.

• | Ignition voltage is 8-18 volts.

### Conditions for Setting the DTC

The control solenoid (w/body and TCM) valve assembly has detected an internal malfunction.

### Action Taken When the DTC Sets

• | DTCs P0601, P0602, P0603, P0604, and P062F are Type A DTCs.

• | The TCM shifts to a default gear, shuts down, and turns OFF.

### Conditions for Clearing the DTC

DTCs P0601, P0602, P0603, P0604, and P062F are Type A DTCs.

### Diagnostic Aids

When attempting to set TCM internal DTCs let the engine run for at least 1 minute and then shut the engine off for 30 seconds. Following this procedure will allow for a complete TCM shutdown. Reprogram the TCM and retest the DTC to see if the DTC resets.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### DTC Type Reference

• | Diagnostic Trouble Code (DTC) Type Definitions

• | Diagnostic Trouble Code (DTC) List/Type

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

### Circuit/System Verification

1. Start the engine.
2. Let the engine run for 1 minute, then shut the engine OFF for 30 seconds.
3. Retest for DTCs P0601, P0602, P0603, P0604, and P062F.

### Circuit/System Testing

Reprogram the TCM and recheck for DTCs.

⇒ | If the DTC resets, replace the control solenoid (w/body and TCM) valve assembly.

### Component Testing

Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Perform the Service Fast Learn Adapts