Life Fitness Lifecycle 3500 Series User manual

Model 3500 Treadmill
SERVICE MANUAL
NET PRICE:
After Market Services

FCC Warning - Possible Radio/Television Interference
NOTE: This equipment has been tested and found to comply with the limits pursuant to Part 15 of the FCC rules. These limits are designed to provide
reasonable protection against harmful interference in a residential installation. Any changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate the equipment. This equipment generates, uses and can radiate radio frequency
energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is
no guarantee that the interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television
reception, which can be determined by turning the equipment off and on, you are encouraged to try to correct the interference by one or more of the
following measures:
•Reorient or relocate the receiving antenna.
•Increase the space between the equipment and the receiver.
•Connect the equipment to an outlet on a different circuit than that to which the receiver is connected.
•Consult an exercise equipment dealer or an experienced radio/TV technician for help.
You are cautioned that any changes or modifications to this equipment could void your product warranty.

Life Fitness Model 3500 Treadmill
INTRODUCTION
HOW TO USE THIS SERVICE MANUAL
In the unlikely event that an operating problem may occur with your Life Fitness model 3500 aerobic trainer, this
Service Manual will instruct and guide you on the quickest, most efficient manner in which to approach the situation.
This Service Manual has been separated into a total of Four Sections for quick reference:
oINTRODUCTION
oTABLE OF CONTENTS
Section I
oTHEORY OF OPERATION
oTROUBLESHOOTING GUIDES
Section II
oDIAGNOSTIC TESTS
Section III
oMODEL 3500 "How To..." GUIDES
Section IV
oWIRING DIAGRAMS
oPARTS IDENTIFICATION
oCOMMUNICATING BY FAX
If an operating problem should arise, turn to the TROUBLESHOOTING GUIDES and attempt to isolate what is causing
the malfunction. The GUIDES are listed by symptoms and follow with suggestions as to the most probable cause of
the problem.
Once you have pinpointed the source of the problem, turn to the appropriate "How To..." section and review the proper
procedures for removing, replacing or adjusting a part. The "How To..." sections are organized by replaceable part (or
assembly) name and each page lists the “Tools Required“ to complete that specific function. Refer to Section IV to
identify the proper name and number of the part you will now need to order to repair your machine. A form to order by
FAX has also been included in Section IV for your convenience.
To order a part, call Life Fitness After Market Services any Monday through Friday from 8:00 AM to 6:00 PM (
C.S.T.). When you place a call, in order to speed our response to your particular situation, please have the following
information available for the customer service phone technician who will be prepared to assist you:
1. The Treadmill model type (3500)
2. The serial number ( Located on the front crossbar between the two wheels)
3. The symptom of the problem you are experiencing
4. The part name and number you need to order
When you receive your order, review the appropriate "How To..." section and follow the step by step procedures
designed to help you install the part quickly and correctly.
If you have any questions or comments please phone, mail, or fax us at one of the numbers listed below.
AFTER MARKET SERVICES
10601 Belmont Avenue, Franklin Park, IL 60131
Phone ( 800 ) 351-3737 Toll Free or ( 708 ) 451-0036
FAX [phone] Toll Free or [phone]
Serial Number:

Life Fitness Model 3500 Treadmill
TABLE OF CONTENTS
INTRODUCTION (How to use this Service Manual)
TABLE OF CONTENTS
SECTION I PAGE
THEORY OF OPERATION 1
TROUBLESHOOTING GUIDES
NO POWER................................................................................................................. 2
NOISY TREADMILL...................................................................................................... 3
STRIDING BELT........................................................................................................... 4
UNIT RESETS RANDOMLY........................................................................................... 5
DISPLAY DOES NOT ILLUMINATE OR RESPOND TO INPUT.......................................... 6
UNIT WILL NOT ELEVATE ............................................................................................ 7
ERROR DISPLAY MESSAGES..................................................................................... 8
HEART RATE DOES NOT RESPOND ........................................................................... 9
(If Equipped with Optional Heart Rate Kit Tray )
SECTION II
DIAGNOSTIC TESTS ................................................................................................................ 1-4
SECTION III
How To...REMOVE AND REPLACE THE
VENT COVER.............................................................................................................. 1
MOTOR COVER........................................................................................................... 2
DISPLAY CONSOLE .................................................................................................... 3
HANDLEBAR AND HANDRAILS .................................................................................... 4
DECK AND STRIDING BELT......................................................................................... 5
FRONT ROLLER ASSEMBLY ....................................................................................... 6
REAR ROLLER ASSEMBLY ......................................................................................... 7
HEATSINK CONTROL BOARD ASSEMBLY ................................................................... 8,9
DISPLAY WIRE HARNESS........................................................................................... 10
LIFT ACTUATOR ASSEMBLY ....................................................................................... 11
DRIVE MOTOR BELT................................................................................................... 12,13
DRIVE MOTOR ASSEMBLY ......................................................................................... 14,15
LIFESPRINGS.............................................................................................................. 16
TRAY ( Optional Heart Rate Kit ).................................................................................... 17
How To...ADJUST AND TENSION THE STRIDING BELT............................................................. 18,19
SECTION IV
WIRING DIAGRAM................................................................................................................... 1
PARTS IDENTIFICATION........................................................................................................... 2,3
COMMUNICATING BY FAX....................................................................................................... 4,5

1
Life Fitness Model 3500 Treadmill
THEORY OF OPERATION
The operational functions of the Life Fitness Model 3500 Treadmill are accomplished by four main components:
The Control Board, the Display Console, the Drive Motor and the Lift Actuator.
The Treadmill user and the Control Board provide input to the Display Console. The Display Console then determines
the appropriate action to be taken and passes low level signals to the Control Board. The Control Board converts low
level signals to high level signals and forwards them to the Drive Motor and the Lift Actuator to execute the requested
command. All of the “Intelligence” within the Treadmill is located in the Display Console.
Control Board
The Control Board provides power for the Treadmill, acts as an interface between the Display Console,
Drive Motor and Lift Actuator, and also acts as an additional interface between the Speed Sensing and
Lift Limit Switches. The Drive Motor trigger, Lift Actuator time and direction, and Safety Power Relay
Signals are received from the Display Console and routed through the Control Board to execute a
command. Speed Sensing and Lift Limit Signals are also passed through the Control Board to the
Display Console.
Display Console
The Display Console is the user interface that allows selection from the various programs and options
offered by the Treadmill. The Display Console provides all of the “Intelligence” within the Treadmill,
controls the Information Displays, and monitors the Keypad and Safety Switches. It determines the
Drive Motor and Lift Actuator actions to suit the chosen Life Fitness aerobic training program and it also
accommodates the optional Heart Rate Receiver.
Drive Motor
The Drive Motor is the component responsible for moving the Striding Belt. The Speed Sensor, located
on the Drive Motor, sends pulses through the Control Board to the Display Console which converts them
to the Striding Belt speed. The Display Console adjusts the power to the Drive Motor to maintain a
constant speed to the Striding Belt resulting in a more comfortable “feel”.
Lift Actuator
The Lift Actuator is the component responsible for raising and lowering the incline level of the Treadmill.
The Display Console, through the Control Board, will raise and lower the Lift Actuator for the appropriate
amount of time and incline required by a specific command. The “Home” Lift Limit Switch signals the
Display Console when the Lift Actuator is at 0% incline. The Lift Actuator also has its own internal built-
in Limit Switches.

2
Life Fitness Model 3500 Treadmill
TROUBLESHOOTING GUIDE
Symptom: NO POWER
Malfunction Probable Cause Corrective Action
No Power On/off switch Turn unit On.
Insufficient power source Plug treadmill into power source with proper
electrical requirements.
(See Operation Manual)
Line cord improperly seated in
electrical outlet Inspect power connection at outlet.
Damaged line cord Replace line cord.
Faulty Display Console See “Display Console “ symptom.

3
Life Fitness Model 3500 Treadmill
TROUBLESHOOTING GUIDE
Symptom: NOISY TREADMILL
Malfunction Probable Cause Corrective Action
Rubbing sound from
beneath machine Foreign objects may be stuck under the machine Inspect underneath Belt and Machine. Remove any debris or accumulation.
Rubbing sound from
Striding Belt Striding Belt not tracking properly
Striding Belt is rubbing on
extrusion or roller pulley
Striding Belt is rubbing on belt
guide
Adjust Striding Belt tracking. See “How
To...Adjust and Tension the Striding Belt”
Center Striding Belt. See “How To...Adjust and
Tension the Striding Belt”
Center Striding Belt. See “How To...Adjust and
Tension the Striding Belt”
Popping sound Insufficient break-in period
Wax accumulation on rear roller
A new Deck and Striding Belt will require a
break-in period of approx. 20 hours.
Run machine at 4 to 5 MPH to distribute wax
onto Striding Belt.
Squeaking noise Lifesprings may be out of
alignment Reposition the Lifesprings.
Drive Motor Belt may be worn or
damaged Replace Drive Motor Belt.
Drive Motor Pulley shifted Check Drive Motor Pulley to insure Pulley is
aligned with Front Roller Pulley. Tighten the
Set Screws to secure the Pulley into place.
“Groaning” sound heard
from front of machine Drive Motor Belt over-tensioned Slacken Drive Belt tension (See “How To...Remove and Replace the Drive Motor Belt”)
Weak Drive Motor/Drive Motor
Software Check Drive Motor Flywheel and Software for compatibility (See Diagnostic Software
Version.
Faulty Drive Motor Replace Drive Motor
Loud “Groaning” sound
heard from front of machine
while elevating
Faulty Lift Motor Perform “Lift Test”. (See Diagnostics).
Replace faulty Lift Motor.

4
Life Fitness Model 3500 Treadmill
TROUBLESHOOTING GUIDE
Symptom: STRIDING BELT
Malfunction Probable Cause Corrective Action
Striding Belt will not move Insufficient power source
Faulty Control Board
Plug treadmill into power source with proper
electrical
requirements. (See Operation Manual)
Replace Control Board
Striding Belt hesitates upon
start up (or will not begin to
turn on new machine)
High amount of friction between
Deck and Striding Belt. Start unit with no one on it at 3.5 mph and 5% or greater incline. Step on to the Belt while it is
moving and walk for 4 to 5 minutes.
Maximum speed reduced Striding Belt, Deck Malfunction
•Deck laminate is worn
through
•Belt worn
Replace Striding Belt and Deck
Line Voltage too low Plug the Treadmill into a power source with the
proper electrical requirements.
Striding Belt slips Adjust Striding Belt Tension (See “How To...”)
Drive Motor Belt slipping See “How To...Remove and Replace the Drive
Motor Belt” for proper Drive Motor Belt
tensioning instructions.
Striding belt comes in
contact with End Caps Unit is not level Adjust rear leveling legs (See Operation Manual)
Striding Belt needs to be re-
tensioned Adjust Striding Belt Tension (See “How To...”)
Missing rubber spacer Replace rubber spacer between Frame and
End Cap
End Cap(s) distorted Replace End Cap(s)
Striding Belt stretched or too
long Replace Deck and Striding Belt

5
Life Fitness Model 3500 Treadmill
TROUBLESHOOTING GUIDE
Symptom: UNIT RESETS RANDOMLY
Malfunction Probable Cause Corrective Action
Unit Resets Randomly Insufficient Power Source Plug Treadmill into power source with proper
electrical requirements. (See Operational
Manual)
Damaged Line Cord Replace Line Cord.
Line Cord improperly seated in
electrical outlet Secure connection at electrical outlet.
Low AC line voltage Too many items tied into AC line. Locate less
used circuit line outlet.

6
Life Fitness Model 3500 Treadmill
TROUBLESHOOTING GUIDE
Symptom: DISPLAY DOES NOT ILLUMINATE OR RESPOND TO INPUT
Malfunction Probable Cause Corrective Action
Display will not illuminate
when machine is turned on. Insufficient power source. Plug Treadmill into power source with proper electrical requirements. (See Operation
Manual)
Loose connection at Display
Console or Control Board. Secure connections at Display Console and Control Board.
Faulty Control Board. With a volt meter check cable voltage at P1
(Console cable) for 8v DC. (pin #2 positive ) (pin
#8 negative).
Faulty Display Console. Replace Display Console.