P179B

DTC P179B

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructionsprovides an overview of each diagnostic category.

DTC Descriptor
DTC P179B
- Range State Command Circuit

Circuit/System Description

This is an internal fault detection of the transmission control module. This fault is handled inside the transmission control module and no external circuits are involved. The transmission control module is part of the control solenoid valve assembly, and is not serviced separately.

Conditions for Running the DTC

* The engine is running.
* Ignition voltage is 8-18 V.

Conditions for Setting the DTC

The control solenoid valve assembly has detected a Range State Command rolling count error for.2 seconds.

Action Taken When the DTC Sets

DTC P179B is a Type A DTC.

Conditions for Clearing the DTC

DTC P179B is a Type A DTC.

Diagnostic Aids

When attempting to set transmission control module internal DTCs, run the engine for at least 1 minute, and then shut the engine OFF for 30 seconds. Following this procedure will allow for a complete transmission control module shutdown. Program the transmission control module with the latest software version and retest the DTC to see if the DTC resets.

Reference Information
Schematic Reference

Automatic Transmission Controls Schematics 2ML70 - Automatic Transmission
Connector End View Reference

Component Connector End Views Connector Views
Electrical Information Reference

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference

Control Module References Control Module Referencesfor scan tool information.

Circuit/System Verification

Verify that DTC P179B is not set.

If the DTC is set, program the Q8 control solenoid valve assembly. If the DTC resets, replace the Q8 control solenoid valve assembly.

Component Testing

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

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Control Module References Control Module Referencesfor Control Solenoid Valve Assembly for replacement, programming and setup.