Horizon
Treadmill

Model # ADVANCE 300 Official Horizon treadmill

Here are the diagrams and repair parts for Official Horizon ADVANCE-300 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 156 parts  |

Nut MZE0204005
Nut

Part #MZE0204005

Replaced by #004926-00

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Manufacturer substitution
This part replaces MZE0204005. Substitute parts can look different from the original.
This item is not returnable
In Stock
Breaker MC0702011
#P04

Treadmill assembly 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

#NI01

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
Rail Lock MB0643001
#Q10

Treadmill assembly 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
Sensor MC0510031D
#P14

Treadmill assembly diagram

Sensor

Part #MC0510031D

Replaced by #002248-D

?
Manufacturer substitution
This part replaces MC0510031D. Substitute parts can look different from the original.
In Stock
Washer MZE0505033
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
Motor Set SZTM59MTR-1
#M01

Treadmill assembly diagram

Motor set

Part #SZTM59MTR-1

Replaced by #016507-Z

?
Manufacturer substitution
This part replaces SZTM59MTR-1. Substitute parts can look different from the original.
$261.04
$12.00 OFF Phone Price : $273.04
In Stock
Screw ME0107015
#M24

Treadmill assembly diagram

Screw

Part #ME0107015

Replaced by #004617-00

?
Manufacturer substitution
This part replaces ME0107015. Substitute parts can look different from the original.
This item is not returnable
In Stock
Screw MZE0104203
#R04

Treadmill assembly diagram

Screw

Part #MZE0104203

Replaced by #004486-00

?
Manufacturer substitution
This part replaces MZE0104203. Substitute parts can look different from the original.
This item is not returnable
In Stock
Bolt MZE0104045
#C18

Treadmill assembly diagram

Bolt

Part #MZE0104045

Replaced by #004462-00

?
Manufacturer substitution
This part replaces MZE0104045. 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.…