Horizon
Treadmill

Model #5.1T Horizon treadmill

Here are the diagrams and repair parts for Horizon 51T treadmill, as well as links to manuals and error code tables, if available.

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    Showing 10 of 162 parts

    Exercise Equipment Retainer Clip

    #Q13

    Treadmill Diagram

    Exercise equipment retainer clip

    Part #005330-00
    ?
    Manufacturer substitution
    This part replaces MZE0701001. Substitute parts can look different from the original.
    This part replaces MZE0701001
    This item is not returnable
    $2.16

    In Stock

    Power Wire (White)

    #P10

    Treadmill Diagram

    Power wire (white)

    Part #002509-A
    ?
    Manufacturer substitution
    This part replaces MC0525027A. Substitute parts can look different from the original.
    This part replaces MC0525027A
    This item is not returnable
    $2.19

    In Stock

    Treadmill Motor Control Board

    #M03

    Treadmill Diagram

    Treadmill motor control board

    Part #013674-DG
    ?
    Manufacturer substitution
    This part replaces SJED08011AA. Substitute parts can look different from the original.
    This part replaces SJED08011AA
    $289.99

    In Stock

    Washer

    #B46

    Treadmill Diagram

    Washer

    Part #MZE0502054

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

    Rubber Pad

    #M07

    Treadmill Diagram

    Rubber pad

    Part #056374-AA
    ?
    Manufacturer substitution
    This part replaces MB0607001B. Substitute parts can look different from the original.
    This part replaces MB0607001B
    This item is not returnable
    $5.66

    In Stock

    Membrane Key

    #N03

    Treadmill Diagram

    Membrane key

    Part #003155-B
    ?
    Manufacturer substitution
    This part replaces MC0602068A. Substitute parts can look different from the original.
    This part replaces MC0602068A
    This item is not returnable
    $5.66

    In Stock

    Nylon Nut

    #L09

    Treadmill Diagram

    Nylon nut

    Part #004949-00
    ?
    Manufacturer substitution
    This part replaces ME0204034. Substitute parts can look different from the original.
    This part replaces ME0204034
    This item is not returnable
    $2.16

    In Stock

    Exercise Equipment Washer

    #K11

    Treadmill Diagram

    Exercise equipment washer

    Part #000491-B
    ?
    Manufacturer substitution
    This part replaces MB0302002. Substitute parts can look different from the original.
    This part replaces MB0302002
    This item is not returnable
    $2.55

    In Stock

    Exercise Equipment Washer

    #R06

    Treadmill Diagram

    Exercise equipment washer

    Part #005106-00
    ?
    Manufacturer substitution
    This part replaces MZE0502129. Substitute parts can look different from the original.
    This part replaces MZE0502129
    This item is not returnable
    $2.57

    In Stock

    Nut Insert

    #B63

    Treadmill Diagram

    Nut insert

    Part #004974-00
    ?
    Manufacturer substitution
    This part replaces MZE0301013. Substitute parts can look different from the original.
    This part replaces MZE0301013
    This item is not returnable
    $2.16

    In Stock

    Symptoms for treadmills

    Choose a symptom to see related treadmill repairs.

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

    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
    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
    June 1, 2015
    By Lyle Weischwill
    How to replace a treadmill walking board

    A worn-out walking board creates friction with the walking belt and causes the belt to slow down during use. Replace the walking board if it's worn or damaged.

    Repair difficulty
    Time required
     30 minutes or less

    Articles and videos for treadmills

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

    June 29, 2015

    Easy DIY treadmill repairs

    By Sears PartsDirect staff

    Learn about treadmill repairs that you can easily do yourself.

    June 1, 2015

    Treadmill common questions

    By Sears PartsDirect staff

    These answers to common questions can help you make the most of your treadmill.

    May 10, 2015

    How to maintain a treadmill

    By Sears PartsDirect staff

    Keep your treadmill in shape by following these tips.