Horizon
Treadmill

Model # QUANTUM II Official Horizon treadmill

Here are the diagrams and repair parts for Official Horizon QUANTUM-II 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 143 parts  |

Switch MC0701002
#P02

Treadmill assembly diagram

Switch

Part #MC0701002

Replaced by #003326-00

?
Manufacturer substitution
This part replaces MC0701002. Substitute parts can look different from the original.
$27.79
18% OFF Phone Price : $33.79
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
In Stock
End Cap MB0609040

#NI05

All parts diagram

End cap

Part #MB0609040

Replaced by #000920-00

?
Manufacturer substitution
This part replaces MB0609040. Substitute parts can look different from the original.
This item is not returnable
In Stock
Pcb Assembly MC0201036A
#M03

Treadmill assembly diagram

Pcb assembly

Part #MC0201036A

Replaced by #013674-DG

?
Manufacturer substitution
This part replaces MC0201036A. Substitute parts can look different from the original.
$416.00
$12.00 OFF Phone Price : $428.00
In Stock
Bolt MZE0121003
Bolt

Part #MZE0121003

Replaced by #004864-00

?
Manufacturer substitution
This part replaces MZE0121003. Substitute parts can look different from the original.
This item is not returnable
In Stock
Sleeve MJ3021002A
#C16

Treadmill assembly diagram

Sleeve

Part #MJ3021002A

Replaced by #008622-B

?
Manufacturer substitution
This part replaces MJ3021002A. Substitute parts can look different from the original.
This item is not returnable
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
Nut MZE0204004
Nut

Part #MZE0204004

Replaced by #004925-00

?
Manufacturer substitution
This part replaces MZE0204004. 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
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

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.…