Horizon
Treadmill

Model # T52 Official Horizon treadmill

Here are the diagrams and repair parts for Official Horizon T52 treadmill, as well as links to manuals and error code tables, if available.

There are a couple of ways to find the part or diagram you need:

  • Click a diagram to see the parts shown on that diagram.
  • In the search box below, enter all or part of the part number or the part’s name.

Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

We encourage you to save the model to your profile, so it’s easy to access parts and manuals for your appliance whenever you log in.

For DIY troubleshooting advice and repair guides, visit our repair help section.

Model diagram and schematic

SEARCH WITHIN THIS MODEL

?

This is the number corresponding to the part on the diagram / schematic

Search
ALL PARTS
Showing 10 of 121 parts  |

Socket MC0703023
#P11

Horizon 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
Nut MZE0204005
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
Breaker MC0702011
#P04

Horizon treadmill diagram

Breaker

Part #MC0702011

Replaced by #003346-00

?
Manufacturer substitution
This part replaces MC0702011. Substitute parts can look different from the original.
In Stock
T-wrench MZE1002003

#NI04

All parts diagram

T-wrench

Part #MZE1002003

Replaced by #005393-00

?
Manufacturer substitution
This part replaces MZE1002003. Substitute parts can look different from the original.
In Stock
Washer MZE0505033
#H27

Horizon treadmill diagram

Washer

Part #MZE0505033

Replaced by #005196-00

?
Manufacturer substitution
This part replaces MZE0505033. Substitute parts can look different from the original.
This item is not returnable
In Stock
Safety Key S140115001
#N24

Horizon treadmill diagram

Safety key

Part #S140115001

Replaced by #016167-Z

?
Manufacturer substitution
This part replaces S140115001. Substitute parts can look different from the original.
Back Order
Wire Harness MC0501136A

#NI01

All parts diagram

Wire harness

Part #MC0501136A

Replaced by #078539

?
Manufacturer substitution
This part replaces MC0501136A. Substitute parts can look different from the original.
In Stock
Screw MZE0104073
#M45

Horizon treadmill diagram

Screw

Part #MZE0104073

Replaced by #004480-Z

?
Manufacturer substitution
This part replaces MZE0104073. Substitute parts can look different from the original.
This item is not returnable
In Stock
Screw MZE0106018
#M14

Horizon treadmill diagram

Screw

Part #MZE0106018

Replaced by #004590-Z

?
Manufacturer substitution
This part replaces MZE0106018. Substitute parts can look different from the original.
This item is not returnable
In Stock
Nut ME0204030
#C23

Horizon treadmill diagram

Nut

Part #ME0204030

Replaced by #004945-00

?
Manufacturer substitution
This part replaces ME0204030. Substitute parts can look different from the original.
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.…