Hendrickson Optimaax 17730-310 Instruction Manual

OPTIMAAX®Lift Axle System
Air Controller Module for
Freightliner Vehicles
SUBJECT: Service Instructions
LIT NO: 17730-310
DATE: January 2024 REVISION: F
TABLE OF CONTENTS
Section 1 Introduction ......................2
Section 2 Product Description ................2
Section 3 Important Safety Notice .............4
Section 4 Denitions .......................8
Section 5 Parts List ........................9
Section 6 Air Controller Module .............10
Section 7 Wiring Diagram ..................11
Section 8 Preventive Maintenance ...........12
Section 9 Air Controller Manifold Diagram .....13
Section 10 Vehicle Air Plumbing Diagram.......15
Section 11 System Operation ................16
Section 12 Diagnostic Tool Software ...........17
Section 13 Troubleshooting Guide.............21

Introduction 217730-310
OPTIMAAX®Lift Axle System Air Controller Module for Freightliner
SECTION 1
Introduction
This publication is intended to acquaint and assist maintenance personnel in the preventive mainte-
nance, service, repair and rebuild of the air controller module for Hendrickson’s OPTIMAAX®Lift Axle
System for Freightliner vehicles.
NOTE Use only Hendrickson genuine parts for servicing this system.
Alteration of the OPTIMAAX system air controller module is not permitted.
It is important to read and understand this entire Technical Procedure publication prior to installation
or performing any maintenance,service, repair, or rebuild of this product.The information in this pub-
lication contains parts lists, safety information, product specifications, features, proper maintenance,
service, repair, and rebuild instructions for the OPTIMAAX system air controller.
Hendrickson reserves the right to make changes and improvements to its products and publications at
any time. Contact Hendrickson Truck Tech Services for information on the latest version of this manual
at 1-866-755-5968 (toll-free U.S. and Canada), 1-630-910-2800 (outside U.S. and Canada) or email:
[email protected].
The latest revision of this publication is also available online at www.hendrickson‑intl.com.
SECTION 2
Product Description
Hendrickson’s OPTIMAAX system is a 6 × 2 solution to help fleets save fuel cost,tire wear, and weight
with comparable handling to 6 × 4 tandem axle configurations. Operating as a liftable axle in the for-
ward tandem position, this system provides versatility for fleets with variable loads.
The OPTIMAAX system air controller monitors the air pressure in the drive axle suspension and calcu-
lates axle load based on air pressure levels.When the load reaches a set threshold (programmed by
Hendrickson, where the limiting factor is typically steer axle load) the OPTIMAAX lift axle automatically
deploys.The OPTIMAAX system air controller module includes the air controller manifold,the electronic
control unit (ECU),and the wiring harness (supplied by Freightliner).
Proprietary program logic controls lift axle movement, load transfer,and braking functions.
■ Fully automated controls — Eliminates driver intervention versus conventional 6x2 manual
control systems.Automates axle lowering and lifting by sensing load capacities.
■ Optimized traction and handling — Lifted axle position provides increased traction by increasing
drive axle load.Improved traction when backing under trailers in soft soil or wet conditions versus
the traditional 6 x 2 configuration. Maintains vehicle handling characteristics by keeping the drive
axle behind the fifth wheel.

17730-310 3Product Description
OPTIMAAX®Lift Axle System Air Controller Module for Freightliner
FIGURE 2‑1 Air Controller Manifold
FIGURE 2‑2 Electronic Control Unit (ECU)
FIGURE 2‑3 Air Controller Wiring Harness (Supplied by Freightliner)
Vehicles built after October 1, 2019
Freightliner Part No.A06-95748-777
HARN-AXLE-LIFT, OL, CHAS F, HDR
Freightliner Part No.A06-95749-000
HARN-AXLE-LIFT, OL, DASH, HDR, P4
Vehicles built prior to October 1, 2019
Freightliner Part No.A06-95715
HARN-AXLE-LIFT, CHAS, HDR
Freightliner Part No.A06-95709
HARN-AXLE-LIFT, DASH, HDR, P4

Important Safety Notice 417730-310
OPTIMAAX®Lift Axle System Air Controller Module for Freightliner
SECTION 3
Important Safety Notice
Proper maintenance, service, and repair is important for the reliable operation of the suspension.The
procedures recommended by Hendrickson and described in this technical publication are methods of
performing such maintenance,service, and repair.
This technical publication should be read carefully to help prevent personal injury and to assure that
proper methods are used.Improper maintenance, service, or repair may damage the vehicle, cause
personal injury,render it unsafe in operation, or void the manufacturer’s warranty.
Failure to follow the safety precautions in this manual can result in personal injury and / or property
damage. Carefully read and understand all safety related information within this publication, on all
decals and in all such materials provided by the vehicle manufacturer before conducting any mainte-
nance,service or repair.
■ EXPLANATION OF SIGNAL WORDS
Hazard“Signal Words”(Danger-Warning-Caution) appear in various locations throughout this publica-
tion.Information accented by one of these signal words must be observed to help minimize the risk of
personal injury to service personnel,or the possibility of improper service methods which may damage
the vehicle or render it unsafe.
This is the safety alert symbol. It is used to alert you to potential personal injury hazards.
Obey all safety messages that follow this symbol to avoid possible injury or death.
Additional Notes or Service Hints are utilized to emphasize areas of procedural importance
and provide suggestions for ease of repair.The following definitions indicate the use of these signal
words as they appear throughout the publication.
INDICATES AN IMMINENTLY HAZARDOUS SITUATION WHICH, IF NOT AVOIDED,WILL RESULT IN SERIOUS
INJURY OR DEATH.
INDICATES A POTENTIAL HAZARDOUS SITUATION WHICH, IF NOT AVOIDED, COULD RESULT IN SERIOUS
INJURY OR DEATH.
INDICATES A POTENTIAL HAZARDOUS SITUATION WHICH, IF NOT AVOIDED, MAY RESULT IN MINOR OR
MODERATE INJURY,OR PROPERTY DAMAGE.
NOTE An operating procedure,practice condition,etc. which is essential to emphasize.
SERVICE HINT A helpful suggestion that will make the servicing being performed a little easier and / or faster.
Also note that particular service operations may require the use of special tools designed for specific
purposes.These special tools can be found in the Special Tools section of this publication.
The torque symbol alerts you to tighten fasteners to a specified torque value. Refer to the Torque
Specifications section in this publication.
The warnings and cautions should be read carefully to help prevent personal injury and to assure that
proper methods are used.Improper maintenance, service, or repair may damage the vehicle, cause
personal injury,render the vehicle unsafe in operation,or void manufacturer’s warranty.

17730-310 5Important Safety Notice
OPTIMAAX®Lift Axle System Air Controller Module for Freightliner
■ SAFETY PRECAUTIONS
FASTENERS
DISCARD USED FASTENERS. ALWAYS USE NEW FASTENERS TO COMPLETE A REPAIR. FAILURE TO DO
SO COULD RESULT IN FAILURE OF THE PART, OR MATING COMPONENTS,ADVERSE VEHICLE HANDLING,
PERSONAL INJURY, OR PROPERTY DAMAGE.
LOOSE OR OVER TORQUED FASTENERS CAN CAUSE COMPONENT DAMAGE, ADVERSE VEHICLE
HANDLING, PROPERTY DAMAGE, OR SEVERE PERSONAL INJURY. MAINTAIN CORRECT TORQUE VALUE
AT ALL TIMES. CHECK TORQUE VALUES ON A REGULAR BASIS AS SPECIFIED, USING A TORQUE WRENCH
THAT IS REGULARLY CALIBRATED.TORQUE VALUES SPECIFIED IN THIS TECHNICAL PUBLICATION ARE FOR
HENDRICKSON SUPPLIED FASTENERS ONLY. IF NON-HENDRICKSON FASTENERS ARE USED, FOLLOW
TORQUE SPECIFICATIONS LISTED IN THE VEHICLE MANUFACTURER’S SERVICE MANUAL.
SUPPORT THE VEHICLE PRIOR TO SERVICING
PLACETHE VEHICLE ON A LEVEL FLOOR AND CHOCK THE WHEELS TO PREVENT THE VEHICLE FROM MOVING
OR ROLLING. DO NOT WORK AROUND OR UNDER A RAISED VEHICLE SUPPORTED BY ONLY A FLOOR JACK.
ALWAYS SUPPORT A RAISED VEHICLE WITH RIGID SAFETY STANDS.FAILURE TO DO SO CAN CAUSE SERIOUS
PERSONAL INJURY OR DAMAGE TO EQUIPMENT.
SUPPORT THE LIFT AXLE PRIOR TO SERVICING
PLACE THE VEHICLE ON A LEVEL FLOOR AND CHOCK THE WHEELS TO HELP PREVENT THE VEHICLE FROM
MOVING. PRIOR TO SERVICING A LIFT AXLE IN THE RAISED POSITION, (1) PROPERLY SUPPORT THE LIFT
AXLE WITH SAFETY STANDS,AND (2) RELEASE ALL AIR PRESSURE IN THE LIFT AXLE AIR SPRINGS AND RIDE
SPRINGS.DO NOT WORK AROUND OR UNDER A RAISED LIFT AXLE SUPPORTED ONLY WITH FLOOR JACKS
OR OTHER LIFTING DEVICES, FAILURE TO DO SO CAN CAUSE DEATH, PERSONAL INJURY, OR DAMAGE TO
COMPONENTS.
PROCEDURES AND TOOLS
A TECHNICIAN USING A SERVICE PROCEDURE OR TOOL WHICH HAS NOT BEEN RECOMMENDED BY
HENDRICKSON MUST FIRST SATISFY THEMSELAVES THAT NEITHER THEIR SAFETY NOR THE VEHICLE’S
SAFETY WILL BE JEOPARDIZED BY THE METHOD OR TOOL SELECTED. INDIVIDUALS DEVIATING IN ANY
MANNER FROM THE INSTRUCTIONS PROVIDED ASSUME ALL RISKS OF POTENTIAL PERSONAL INJURY OR
DAMAGE TO EQUIPMENT INVOLVED.
PERSONNEL PROTECTIVE EQUIPMENT
ALWAYS WEAR PROPER EYE PROTECTION AND OTHER REQUIRED PERSONAL PROTECTIVE EQUIPMENT TO
HELP PREVENT PERSONAL INJURY WHEN PERFORMING VEHICLE MAINTENANCE,REPAIR OR SERVICE.
MODIFYING COMPONENTS
DO NOT MODIFY OR REWORK PARTS WITHOUT AUTHORIZATION FROM HENDRICKSON. DO NOT
SUBSTITUTE REPLACEMENT COMPONENTS NOT AUTHORIZED BY HENDRICKSON. USE OF MODIFIED,
REWORKED, SUBSTITUTE OR REPLACEMENT PARTS NOT AUTHORIZED BY HENDRICKSON MAY NOT MEET
HENDRICKSON’S SPECIFICATIONS,AND CAN RESULT IN FAILURE OF THE PART,ADVERSE VEHICLE HANDLING,
POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE,AND WILL VOID ANY APPLICABLE WARRANTIES.USE
ONLY HENDRICKSON AUTHORIZED REPLACEMENT PARTS.
ELECTRICAL SYSTEM
DO NOT WORK ON THE VEHICLE ELECTRICAL SYSTEM WITH THE VEHICLE POWER ON. DAMAGE TO THE
VEHICLE‘S ELECTRICAL SYSTEM AND / OR UNEXPECTED AXLE MOVEMENT MAY RESULT.
WIRING HARNESS
ENSURE THERE IS SUFFICIENT FREE MOVEMENT IN THE AIR CONTROLLER WIRING HARNESS TO PREVENT
WIRES AND CONNECTIONS FROM BEING UNDER TENSION DURING INSTALLATION. FAILURE TO DO SO MAY
DAMAGE OR FRAY THE CABLES.