2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1731

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1731

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions)provides an overview of each diagnostic category.

DTC Descriptor

DTC P071A

- Transmission Tow Mode Switch Circuit

Circuit/System Description

Tow/haul mode enables the operator to achieve enhanced shift performance when towing or hauling a load. When tow/haul mode is selected, the

tow/haul switch input signal to the body control module (BCM) is momentarily toggled to zero volts. This signals the transmission control module

(TCM) to extend the length of time between upshifts and increase transmission line pressure. Cycling the tow/haul switch again disables tow/haul

mode and returns the transmission to a normal shift pattern.

Conditions for Running the DTC

* No Transmission Mode Switch Signal DTC P1762.

* The engine speed is greater than 500 RPM for 5 seconds.

* The system voltage is 8-18 volts.

Conditions for Setting the DTC

The Tow Mode switch remains closed, low voltage, for 600 seconds.

Action Taken When the DTC Sets

DTC P071A is a Type C DTC.

Conditions for Clearing the DTC

DTC P071A is a Type C DTC.

Diagnostic Aids

If the electrical circuit tests are OK and the shift pattern is not occurring, there may be a mechanical/hydraulic condition that prevents operation.

Refer to Symptoms - Automatic Transmission (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing and

Inspection/Symptom Related Diagnostic Procedures/6L45/6L50/6L80/6L90 - Automatic Transmission/Symptoms - Automatic Transmission).

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Diagrams)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Description and Operation

Electronic Component Description (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and

Operation/6L45/6L50/6L80/6L90 - Automatic Transmission/Electronic Component Description)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)