Horizon
Treadmill

Model #CST3.5X Horizon treadmill

Here are the diagrams and repair parts for Horizon CST35X treadmill, as well as links to manuals and error code tables, if available.


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Showing 10 of 143 parts

Exercise Equipment Washer

#H20

Treadmill Diagram

Exercise equipment washer

Part #005035-00
?
Manufacturer substitution
This part replaces MZE0502014. Substitute parts can look different from the original.
This part replaces MZE0502014
This item is not returnable
$2.47

In Stock

Washer

#H22

Treadmill Diagram

Washer

Part #005232-A
?
Manufacturer substitution
This part replaces MZE0506020A. Substitute parts can look different from the original.
This part replaces MZE0506020A
This item is not returnable
$2.16

In Stock

Treadmill Nut

#R10

Treadmill Diagram

Treadmill nut

Part #004903-Z
?
Manufacturer substitution
This part replaces MZE0201038. Substitute parts can look different from the original.
This part replaces MZE0201038
This item is not returnable
$2.16

In Stock

Treadmill Screw

#M45

Treadmill Diagram

Treadmill screw

Part #004480-Z
?
Manufacturer substitution
This part replaces MZE0104073. Substitute parts can look different from the original.
This part replaces MZE0104073
This item is not returnable
$2.16

In Stock

Exercise Equipment Screw

#P13

Treadmill Diagram

Exercise equipment screw

Part #004415-Z
?
Manufacturer substitution
This part replaces MZE0103001. Substitute parts can look different from the original.
This part replaces MZE0103001
This item is not returnable
$2.16

In Stock

Exercise Equipment Nut

#H51

Treadmill Diagram

Exercise equipment nut

Part #004941-00
?
Manufacturer substitution
This part replaces ME0204025. Substitute parts can look different from the original.
This part replaces ME0204025
This item is not returnable
$2.16

In Stock

Tube-r

#C28

Treadmill Diagram

Tube-r

Part #015126-AA
?
Manufacturer substitution
This part replaces SP0050002AA. Substitute parts can look different from the original.
This part replaces SP0050002AA
$24.94

Back Order

Tie Strap Adhesive

#KIT

Treadmill Diagram

Tie strap adhesive

Part #001679-00
?
Manufacturer substitution
This part replaces MB0906002. Substitute parts can look different from the original.
This part replaces MB0906002
This item is not returnable
$2.16

In Stock

Screw

#Q32

Treadmill Diagram

Screw

Part #020186-00
?
Manufacturer substitution
This part replaces MZE0107047. Substitute parts can look different from the original.
This part replaces MZE0107047
This item is not returnable
$2.16

In Stock

Treadmill Power Cord Receptacle

#P11

Treadmill Diagram

Treadmill power cord receptacle

Part #019749-A
?
Manufacturer substitution
This part replaces MC0703023. Substitute parts can look different from the original.
This part replaces MC0703023
$7.98

In Stock

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor
Main causes: faulty sensors, wiring failure, bad control console
Main causes: missing safety key, bad control console, wiring failure, faulty motor control board, bad drive motor
Main causes: rear roller out of alignment, damaged walking belt, bad roller
Main causes: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor control board
Main causes: bad control console, wiring failure, bad motor control board
Main causes: damaged walking belt, improper belt tension, bad roller bearing

Repair guides for treadmills

These step-by-step repair guides will help you safely fix what’s broken on your treadmill.

June 1, 2015
By Lyle Weischwill
How to replace a treadmill drive motor

A defective drive motor won't run when activated by the motor controller. Replace the treadmill drive motor if it doesn't run.

Repair difficulty
Time required
 15 minutes or less
June 1, 2015
By Lyle Weischwill
How to replace a treadmill motor controller

Your treadmill motor won't run with a defective motor controller. Replace the motor controller if it doesn't operate the motor correctly.

Repair difficulty
Time required
 15 minutes or less
June 1, 2015
By Lyle Weischwill
How to replace a treadmill walking board

A worn-out walking board creates friction with the walking belt and causes the belt to slow down during use. Replace the walking board if it's worn or damaged.

Repair difficulty
Time required
 30 minutes or less

Articles and videos for treadmills

Use the advice and tips in these articles and videos to get the most out of your treadmill.

January 18, 2016

How to use a multimeter to test electrical parts video

By Sears PartsDirect staff

Learn how to use a multimeter to check for wiring problems in an appliance that's not working

June 29, 2015

Easy DIY treadmill repairs

By Sears PartsDirect staff

Learn about treadmill repairs that you can easily do yourself.

June 1, 2015

Treadmill common questions

By Sears PartsDirect staff

These answers to common questions can help you make the most of your treadmill.