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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

?
Manufacturer substitution
This part replaces MZE0204005. Substitute parts can look different from the original.
This item is not returnable
$2.16
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.
$14.80
In Stock
Wheel MB0103006B
#L05

Treadmill assembly diagram

Wheel

Part #MB0103006B

Replaced by #000021-B

?
Manufacturer substitution
This part replaces MB0103006B. Substitute parts can look different from the original.
This item is not returnable
$5.25
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
$3.92
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.
$8.16
In Stock
Holder MB0668001B
#N17

Treadmill assembly diagram

Holder

Part #MB0668001B

Replaced by #001363-B

?
Manufacturer substitution
This part replaces MB0668001B. Substitute parts can look different from the original.
This item is not returnable
$2.53
In Stock
Screw MZE0106017
#M10

Treadmill assembly diagram

Screw

Part #MZE0106017

Replaced by #004589-00

?
Manufacturer substitution
This part replaces MZE0106017. Substitute parts can look different from the original.
This item is not returnable
$2.16
In Stock
Screw ME0123003
#Q11

Treadmill assembly diagram

Screw

Part #ME0123003

Replaced by #004870-00

?
Manufacturer substitution
This part replaces ME0123003. Substitute parts can look different from the original.
This item is not returnable
$2.16
In Stock
Bolt MJ3027002A
#L14

Treadmill assembly diagram

Bolt

Part #MJ3027002A

Replaced by #008641-C

?
Manufacturer substitution
This part replaces MJ3027002A. Substitute parts can look different from the original.
This item is not returnable
$2.16
In Stock
Lock Ring MB0302002
#K11

Treadmill assembly diagram

Lock ring

Part #MB0302002

Replaced by #000491-B

?
Manufacturer substitution
This part replaces MB0302002. Substitute parts can look different from the original.
This item is not returnable
$2.59
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…

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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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