Horizon
Treadmill

Model # CST3 Official Horizon treadmill

Here are the diagrams and repair parts for Official Horizon CST3 treadmill, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 132 parts  |

Controller SZTM113MCB
#M03

Treadmill diagram

Controller

Part #SZTM113MCB

Replaced by #032669-IF

?
Manufacturer substitution
This part replaces SZTM113MCB. Substitute parts can look different from the original.
This item is not returnable
$220.61
5% OFF Phone Price : $232.61
In Stock
Nut MZE0204005
#H26

Treadmill diagram

Nut

Part #MZE0204005

Replaced by #004926-00

?
Manufacturer substitution
This part replaces MZE0204005. Substitute parts can look different from the original.
This item is not returnable
In Stock
Bottle Set MF0821002A
#NI

Treadmill diagram

Bottle set

Part #MF0821002A

Replaced by #1000092805

?
Manufacturer substitution
This part replaces MF0821002A. Substitute parts can look different from the original.
This item is not returnable
$16.01
11% OFF Phone Price : $18.01
Back Order
Socket MC0703023
#P11

Treadmill diagram

Socket

Part #MC0703023

Replaced by #019749-A

?
Manufacturer substitution
This part replaces MC0703023. Substitute parts can look different from the original.
This item is not returnable
$9.62
9% OFF Phone Price : $10.62
In Stock
Elastomer MB0502016D
#B57

Treadmill diagram

Elastomer

Part #MB0502016D

Replaced by #000767-D

?
Manufacturer substitution
This part replaces MB0502016D. Substitute parts can look different from the original.
$17.69
10% OFF Phone Price : $19.69
In Stock
Elastomer MB0502017D
#B58

Treadmill diagram

Elastomer

Part #MB0502017D

Replaced by #000768-D

?
Manufacturer substitution
This part replaces MB0502017D. Substitute parts can look different from the original.
In Stock
Drive Mtr SZTM113MTR
#M01

Treadmill diagram

Drive mtr

Part #SZTM113MTR

Replaced by #1000111822

?
Manufacturer substitution
This part replaces SZTM113MTR. Substitute parts can look different from the original.
$300.86
10% OFF Was : $334.29
In Stock
Drive Belt MD0602001
#R03

Treadmill diagram

Drive belt

Part #MD0602001

Replaced by #1000109551

?
Manufacturer substitution
This part replaces MD0602001. Substitute parts can look different from the original.
$55.69
10% OFF Phone Price : $61.69
In Stock
Reed Switch MC0403014A
#N13

Treadmill diagram

Reed switch

Part #MC0403014A

Replaced by #001963-A

?
Manufacturer substitution
This part replaces MC0403014A. Substitute parts can look different from the original.
This item is not returnable
In Stock
Membr Key MC0602195A
#N06

Treadmill diagram

Membr key

Part #MC0602195A

This item is not returnable
In Stock

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

Main causes: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor co…

Main causes: rear roller out of alignment, damaged walking belt, bad roller…

Main causes: missing safety key, bad control console, wiring failure, faulty motor control board, bad drive motor…

Main causes: faulty sensors, wiring failure, bad control console…

Main causes: bad control console, wiring failure, bad motor control board…

Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor…

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.

How to replace a treadmill motor controller

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…

Repair difficulty
Time required
 15 minutes or less
How to replace a treadmill walking belt

How to replace a treadmill walking belt

A worn walking belt will begin to slow down during use. If your treadmill walking belt is worn out, replace it using the…

Repair difficulty
Time required
 45 minutes or less
How to replace a treadmill drive motor

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'…

Repair difficulty
Time required
 15 minutes or less

Effective articles & videos to help repair your fitness & exercise

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

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…