General Motors QuadraSteer training manual

Course 13041.20D

Rear Wheel Steering

™

(QUADRASTEER

Service Technical College

)

Participant Guide Revised: 10/16/06

Caution

In order to reduce the risk of personal injury or property damage, carefully observe the following information:

The service manuals of General Motors Corporation are intended for use by professional, qualified technicians. Attempting service procedures without the appropriate training, tools, and equipment could cause personal injury, vehicle damage, or improper vehicle operation. Proper vehicle service is important to the safety of the service technician and to the safe, reliable operation of all motor vehicles. If a replacement part is needed, use the same part number or an equivalent part. Do not use a replacement part of lesser quality.

The service manuals contain effective methods for performing service procedures. Some of the procedures require the use of tools that are designed for specific purposes.

Accordingly, any person who intends to use a replacement part, a service procedure, or a tool that is not recommended by General Motors, must first establish that there is no jeopardy to personal safety or the safe operation of the vehicle.

The service manuals contain Cautions and Notices that must be observed carefully in order to reduce the risk of personal injury. Improper service may cause vehicle damage or render the vehicle unsafe. The Cautions and Notices are not all-inclusive. General Motors can not possibly warn of all the potentially hazardous consequences that may result by not following the proper service procedures.

The service manuals cover service procedures for vehicles that are equipped with Supplemental Inflatable Restraints (SIR). Failure to observe all SIR Cautions and Notices could cause air bag deployment, personal injury, or otherwise unneeded SIR repairs. Refer to the SIR component and wiring location views in Restraints before performing a service on or around SIR components or wiring.

If multiple vehicle systems are in need of repair, including SIR, repair the SIR system first to reduce the risk of accidental air bag deployment and personal injury.

January 2002

Table of Contents

Welcome and System Instructions .......................................................................i

Introduction ....................................................................................................... i-1

Module 1: Rear Wheel Steering System Introduction .....................................1-1

Module 2: Rear Wheel Steering System Operation ........................................2-1

Module 3: Four Wheel Steering Alignment......................................................3-1

Appendix..........................................................................................................A-1

Evaluation.........................................................................................................E-1

Instructor:

This manual contains information about service for the Rear Wheel Steering System. Always refer to applicable vehicle service information and appropriate Dealer Technical Service Bulletins for additional information regarding system operation and diagnostic/repair procedures. When this manual refers to a brand name, a number, or a specific tool, you may use an equivalent product in place of the recommended item.

All information, illustrations and specifications in this manual are based on the latest product information available at the time of publication approval. General Motors reserves the right to make changes at any time without notice.

No part of this book may be reproduced, stored in any retrieval system, or transmitted in any form or by any means (including but not limited to electronic, mechanical, photocopying, and recording) without prior written permission of General Motors Corporation. This applies to all text, illustrations, tables and charts.

is a registered treademark of Delphi Automotive Systems, Inc.

i Rear Wheel Steering (QUADRASTEERTM)

Welcome to Rear Wheel Steering (QUADRASTEERTM)

Before the broadcast begins, please read the following information which will help you understand the One Touch site controller and keypad — your links to the instructor and the other course participants.

Using One Touch

1) Logging in to the system

To log in to the system, follow these steps:

1. Verify correct HOST number for your session by referring to the Host number that appears in the lower, right corner of the TV screen during the broadcast.

2. Check the Host Number that appears on your OneTouch site controller, which is the large black box located near your TV equipment. If necessary , use the Plus (+) or Minus (-) key on the site controller's display to change the host to the correct number, and then press the Enter Key (↵) to log onto the host.

3. Once the keypad asks for you ID, enter your student identification number. (U.S. Social Security, Canadian EIN or Mexican IMSS or Person ID, effective January 2005) on your OneTouch keypad, and then press the Enter Key. The message "Validating" appears on the keypad for a few seconds. Next, your name appears. this confirms that you have logged onto a host.

NOTE: If you have already logged in to your keypad and you determine that our site controller is NOT set to the correct host number , you must first log off the site controller by pressing the Esc key on the site controller's display. W ait until the sytem logs you off, and then follow the steps above for logging back into the system.

Finally , if you are experiencing any technical difficulties and are unable to log in on both the keypad and the site controller, please call the GM T raining Help Desk at 1-888-

748-2687 and press prompt 1.

2) Speaking to the Instructor

For best results while speaking to the instructor, follow these tips:

1. Place the keypad near the front of your desk. Put your class materials between you and the keypad.

Speak directly into the microphone on the keyp ad. The microphone is located just

below the row of five function keys. Speak in a normal tone from your standard seated position. You will be heard by all of the other course participants and the instructor.

System Instructions ii

Using the Keypad

If you want to...

Ask a question, make a comment, enter a discussion, or cancel a call to the instructor.

Signal the instructor anonymously that you do not understand.

Answer a multiple-choice question.

Answer a question with a numeric answer.

press: and this will happen...

Your WAIT light will be turned on and your

Call

Flag

BCDE

Enter

name will be added to the queue. Your SPEAK light will come on when it is your turn to speak. If you press the CALL key a second time, your WAIT light will go off, and your call will be canceled.

The percentage of students signaling the instructor is displayed on the instructors monitor. The instructor may adjust the lecture accordingly.

If you are taking a multiple question quiz, the answer is stored until you answer the last question. On single questions the answer is transmitted to the host site when you press the ANSWER key.

If you are taking a multiple questions quiz the answer is stored until you answer the last question. On single questions,the answer is transmitted to the host site when you press the ENTER key.

Erase a numeric answer.

See the next quiz questions answer set, and any response you may have entered for that question.

See the previous quiz questions answer set, and any response you may have entered for that question

GM Training Help Desk  1-888-748-2687

Clear

Quest

Ques

NOTE: To confirm that your response has been received by the system, your letter or number choice will be found in brackets in the upper right-hand corner of the keypad display.

The answer in the window will be erased. On single questions, you must press CLEAR before you press ENTER.

The next questions ID and answer character set will appear on the keypad display. If you have already answered the question, your answer will also display.

The previous questions ID and answer character set will appear on the keypad display. If you have already answered the question, your answer will also display.

Rear Wheel Steering

(QUADRASTEER

Introduction

)

Introduction i-1

Welcome

Welcome to Rear Wheel Steering (QUADRASTEERTM)

One Touch Familiarization

• Press the red call button to ask a question

• Wait for a green light before speaking

• Anticipate a momentary delay when speaking

• Contact the Technical help desk at 1-888-748-2687, prompt 1, if necessary

Question 1

In which of the following regions is your dealership located?

Course Goal

Upon successful completion of this course, you will be able to identify the Rear Wheel Steering System, associated components and apply concepts and procedures to diagnose the system operation.

Session Objectives

 Identify the Rear Wheel Steering

System and its benefits

 Identify system components and their

roles in operation

 Identify unique system features  Identify diagnostic procedures

A. Atlanta B. Chicago C. Dallas D. Los Angeles E. New York

Question 2

Which of the following best describes your experience level at GM dealerships?

A . Greater than 10 years B. Between 5-10 years C. Between 2-5 years D. Less than 2 years

Strategy Based Diagnostics

Step 1. Verify customer concern Step 2. Make quick checks Step 3. Follow diagnostic system checks Step 4. Check service bulletins Step 5. Diagnostics Step 6. Decision on cause isolation Step 7. Repair and verification

Special Instructions

The diagnostic charts in this courseware are for reference only. Refer to Service Information when servicing Rear Wheel Steering Systems.

i- 2 Rear Wheel Steering (QUADRASTEERTM)

STC T raining Courses*

Video CBT IDL Hands-On

1–Component Course

2–Component Course

3–Component Course

* Sample course component combinations

*Course Components

•A 1-component course has no recommended prerequisite(s) or follow-up component

•A 2-component course has a recommended prerequisite(s) CBT or Video component which you should complete before attending the IDL (or) it consists of an IDL or CBT followed by a Hands-On component which you will need to take in order to complete the course

•A 3-component course has a recommended prerequisite(s) CBT or Video component which should be completed before attending the IDL. You will need to take the follow-up Hands-On component in order to complete the entire course

The dealership STS Report is credited when all components of the course are completed.

NOTICE: You’ll see your Training Record and Individual Training Plan change as each course component is successfully completed. Just visit www.gmtraining.com and check TMS.

To purchase authentic GM Service Training Materials,

contact the GM Training Materials Headquarters at 800-393-4831.

Rear Wheel Steering

(QUADRASTEER™)

Module 1

Rear Wheel Steering Introduction

Rear Wheel Steering System Introduction 1-1

Module 1 Objectives

 Identify the benefits of the Rear Wheel

Steering System

 Describe the three phases of

operation

 Describe the three modes of operation  Identify system components and

operation

Turning Radius

 Identify the cautions associated with

using in-ground hoist/jack stand

Rear Wheel Steering System Benefits

The Rear Wheel Steering System, in combination with the front steering system, offers several benefits over typical non-rear steering systems:

• Reduced turning radius

• Increased stability during high-speed maneuvers such as passing and lane changes

• Increased maneuverability when towing a trailer

• Better maneuverability during low-speed maneuvers such as parking

T urning Radius

The turning radius of a vehicle is significantly enhanced with Rear Wheel Steering.

 The turning radius of the GMC Sierra with

Rear Wheel Steering can be compared to the turning radius of a Saturn Sedan

1-2 Rear Wheel Steering (QUADRASTEER™)

Driving Phases

Depending on the various inputs communicated to the controller, the system operates in one of three phases:

Negative Phase

• Used during low-speed maneuvers for increased maneuverability

• Steers the wheels in the opposite direction of the front wheels

Negative Phase

Neutral Phase

• Between zero and 45 mph (approximately)

Neutral Phase

• Used during front-wheel only steering

• Rear wheels remain in a straight ahead position no matter what direction the front wheels turn

• It is the fail-safe phase of operation

• 45 mph (approximately)

Positive Phase

• Used during high-speed maneuvers and when towing a trailer at high speeds for increased stability

• Steers the rear wheels in the same direction as the front wheels

• 45 mph and above (approximately)

The changes between the phases are subtle, gradual changes.

Positive Phase

Rear Wheel Steering System Introduction 1-3

High-Speed St ability , T railering Maneuverability , and Low-S peed Maneuverability

These videos demonstrate how the combined steering of the front and rear wheels improves the truck’s maneuverability. These three video segments will show high speed stability, enhanced trailering and improved maneuverability during parking.

Video Outline – High-Speed Stability

• The Rear Wheel Steering System helps improve stability during high-speed lane changes

Front and Rear Wheels Turned in Same Direction

• With the Mode Select Switch in the 4-wheel steer position, the front and rear wheels turn in the same direction during high-speed maneuvers

• When both the front and rear wheels turn in the same direction, the system is operating in the positive phase

• Positive phase Rear Wheel Steering improves stability during higher-speed maneuvers

Video Notes:

Lateral Motion Affected by Direction Changes in Wheel Angle

1-4 Rear Wheel Steering (QUADRASTEER™)

Video Outline cont. – Trailering Maneuverability

• Stability of Rear Wheel Steering continues with a trailer attached

• System continues operating in positive phase, allowing the trailer to track the truck more directly

• With Rear Wheel Steering, backing and parking a trailer becomes easier, particularly when additional maneuvering

Lane-Change when Towing a Trailer

space isn’t available

• When operating at slow speeds in the tow mode, the rear wheels turn in the opposite direction of the front wheels

Vehicle Parking with a Trailer Attached

• Allows for much easier maneuvering of the trailer, particularly in tight spots

Video Notes:

Front Wheel and Rear Wheel Turning in Opposite Directions

Rear Wheel Steering System Introduction 1-5

Video Outline cont. – Low-Speed Maneuverability

• Normal vehicle parking, especially in tight parking spaces, also becomes much easier with Rear Wheel Steering

• With the Mode Select Switch in the 4-wheel steer position, the front and rear wheels turn in the opposite direction during low-speed maneuvers, such as parking

• When the front and rear wheels turn in the opposite direction, the system is operating in the negative phase

• Negative phase Rear Wheel Steering improves maneuverability while operating at low speeds

Video Notes:

Vehicle Pulling into Parking Spot

Front and Rear Wheels Turning in Opposite Directions

Why do we use a 5º positive phase steering vs. a 12º negative phase?

1-6 Rear Wheel Steering (QUADRASTEER™)

Modes of Operation

Video Outline –

The modes of operation steer by using the driving phases.

 2-Wheel Steer

• Steering Wheel Position Sensor – base of steering column

Component Locations

– Conventional front steering

 4-Wheel Steer

– Conventional front steering with rear

wheel steer

 4-Wheel Steer Tow

– Conventional front steering with rear

wheel steering optimized for towing

Rear steering angle is determined based on:

• Mode selection by the driver

• Speed of the vehicle

Component Locations

The video on component locations demonstrates the visual placement of each component in the system.

• Mode Select Switch – instrument panel

• Yaw Rate and Lateral Accelerometer – beneath front passenger seat (Removed in MY04)

• Vehicle Speed Sensor – transmission housing

• Steerable Rear Axle – normal rear axle position

• Difference is steerable rear axle includes quarter shafts with steering components on ends of quarter shafts

• Rear Wheel Steering Control Module – frame mounted on rear undercarriage of vehicle

• Rear Actuator – positioned on rear axle and consists of:

- Inner and outer tie rods

- Rear Position Sensor

- Steering gear motor

- Rack and pinion assembly with boots

• Wiring Harness – subsystem of the vehicle harness

Component Locations

Rear Wheel Steering System Introduction 1-7

TECH TIP

Caution When lifting the vehicle using an in-

ground hoist or supporting the axle with jack stands, it’s very important that the hoist is positioned at the correct lifting points on the vehicle. If not, boot damage may occur.

• Notice how close the lift point is to the boots

• Use caution when lifting this vehicle

Correct Lift Points (Circled)

• The recommended method to lift the vehicle is using an above ground hoist

• Use current Service Information for details: – Select "General Information" and then

"General Information " again. Next select "Introduction". Finally select "Lifting and Jacking the Vehicle".

Video Notes:

1-8 Rear Wheel Steering (QUADRASTEER™)

Fill in the blanks on the illustration below with the letter for each component shown in the list.

Exercise: Component Locations

Components

A. Steering Wheel Position

Sensor B. Vehicle Speed Sensor C. Mode Select Switch D. Control Module E. Steerable Rear Axle

Identify any one of the three inputs and its purpose.

TECH TIP

GM recommends you do not use tire chains with the Rear Wheel Steering System. The chains could hit the wheel housing when the wheels are turning left or right. If you must use chains, keep the vehicle in 2WS mode.

Hit your flag key when finished.

TECH TIP

Do NOT change the tire size. This may cause interference with the wheel housing and calibration concerns with the ABS, PCM and the Rear Wheel Steering Module.

Module 1 Summary

 Benefits of System  Three Phases of Operation  Three Modes of Operation  System Components and Operation  Caution When Using In-Ground Hoist/Jack

Stand

+ 44 hidden pages

General Motors QuadraSteer training manual

Specifications and Main Features

Frequently Asked Questions

User Manual