Horizon
Treadmill

Model #RT1 Official Horizon treadmill

Here are the diagrams and repair parts for Horizon RT1 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”.

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

Installation guide

Showing 10 of 135 parts

Treadmill On/Off Switch#P02

Cycle Diagram

Switch

Part #MC0701002
Replaced by #003326-00
?
Manufacturer substitution
This part replaces MC0701002. Substitute parts can look different from the original.
In Stock
$27.79 | 
15% OFF 
Phone Price: $32.79
Screw#N73

Cycle Diagram

Screw

Part #MZE0102013

The manufacturer no longer makes this part, and there's no substitute part

Treadmill Rear Roller#AR2

Cycle Diagram

Roller

Part #MR0902010D
Replaced by #1000108449
?
Manufacturer substitution
This part replaces MR0902010D. Substitute parts can look different from the original.
In Stock
$147.39 | 
6% OFF 
Phone Price: $157.39
C-Clip#H24

Cycle Diagram

C-clip

Part #MZE0902005
Replaced by #005360-00
?
Manufacturer substitution
This part replaces MZE0902005. Substitute parts can look different from the original.
This item is not returnable
In Stock
$2.49
Core#M17

Cycle Diagram

Core

Part #MC0704005
Replaced by #003386-A
?
Manufacturer substitution
This part replaces MC0704005. Substitute parts can look different from the original.
In Stock
$12.13
Fix Plate#L10

Cycle 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
In Stock
$3.92
Bolt#B41

Cycle Diagram

Shock

Part #MJ3011001
Replaced by #008609-00
?
Manufacturer substitution
This part replaces MJ3011001. Substitute parts can look different from the original.
This item is not returnable
In Stock
$5.93
Sleeve#C11

Cycle Diagram

Sleeve

Part #MD0504024A
Replaced by #004123-A
?
Manufacturer substitution
This part replaces MD0504024A. Substitute parts can look different from the original.
This item is not returnable
In Stock
$3.05
Washer#H21

Cycle Diagram

Washer

Part #MZE0502197A

The manufacturer no longer makes this part, and there's no substitute part

Nut

See All Related Diagrams

Nut

Part #MZE0203008

The manufacturer no longer makes this part, and there's no substitute part

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

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

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 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
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 these steps.

Repair difficulty
Time required
 45 minutes or less
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

Articles and videos common to all fitness & exercise

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

June 29, 2022

Top questions about Sears and Sears PartsDirect

By Lyle Weischwill

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