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Horizon
Treadmill

Model # DT850 Official Horizon treadmill

Here are the diagrams and repair parts for Official Horizon DT850 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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ALL PARTS
Showing 10 of 148 parts  |
Controller SZTM113MCB
#M03

Treadmill assy diagram

Controller

Part #SZTM113MCB

Replaced by #032669-IF

?
Manufacturer substitution
This part replaces SZTM113MCB. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$220.62 | 
$10.00 OFF Phone Price : $230.62
In Stock
Socket MC0703023
#P11

Treadmill assy 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
Rail Lock MB0643001
#L10

Treadmill assy diagram

Rail lock

Part #MB0643001

Replaced by #001251-F

?
Manufacturer substitution
This part replaces MB0643001. Substitute parts can look different from the original.
This item is not returnable
$3.92
In Stock
Ac Cord MC0504054A
#P07

Treadmill assy diagram

Ac cord

Part #MC0504054A

Replaced by #002169-A

?
Manufacturer substitution
This part replaces MC0504054A. Substitute parts can look different from the original.
$46.34 | 
10% OFF Was : $51.49
In Stock
Wheel MB0103040CA
Wheel

Part #MB0103040CA

Replaced by #000037-CA

?
Manufacturer substitution
This part replaces MB0103040CA. Substitute parts can look different from the original.
This item is not returnable
$2.26
In Stock
Deck Bolt MZE0105005
#B36

Treadmill assy diagram

Deck bolt

Part #MZE0105005

Replaced by #004562-00

?
Manufacturer substitution
This part replaces MZE0105005. Substitute parts can look different from the original.
This item is not returnable
$2.16
In Stock
Cable MC0503001B
#P08

Treadmill assy diagram

Cable

Part #MC0503001B

Replaced by #002124-B

?
Manufacturer substitution
This part replaces MC0503001B. Substitute parts can look different from the original.
This item is not returnable
$4.47
In Stock
Screw ME0102042
#P17

Treadmill assy diagram

Screw

Part #ME0102042

Replaced by #004381-00

?
Manufacturer substitution
This part replaces ME0102042. Substitute parts can look different from the original.
This item is not returnable
$2.16
In Stock
Belt MD0602023
#R03

Treadmill assy diagram

Belt

Part #MD0602023

Replaced by #1000109577

?
Manufacturer substitution
This part replaces MD0602023. Substitute parts can look different from the original.
$57.97
In Stock
Decal,cons MG0256200A
#V23

Treadmill assy diagram

Decal,cons

Part #MG0256200A

Replaced by #021541-AX

?
Manufacturer substitution
This part replaces MG0256200A. Substitute parts can look different from the original.
This item is not returnable
$2.16
In Stock

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

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Why won't my treadmill power up?

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

Read more

Why is my treadmill's walking belt off center?

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

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Why won't my treadmill start even though the console display works?

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

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Why is my treadmill's heart rate sensor not accurate?

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

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Why does my treadmill have no display?

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

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Why does my treadmill's walking belt slow down?

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

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Why is my treadmill's walking belt slipping?

Main causes: damaged walking belt, improper belt tension, bad roller bearing…

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Repair guides for treadmills

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

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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…

Read more
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…

Read more
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'…

Read more
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.

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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.…

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