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DP 21-3900A treadmill

DP 21-3900A treadmill Parts

Here are the diagrams and repair parts for DP 21-3900A treadmill, as well as links to manuals and error code tables, if available.

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Browse Parts for 21-3900A Fitness & Exercise

  • Monitor for DP 21-3900A - Part 37036800

    Control panel diagram

    Monitor

    Part #37036800

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

  • Motor Cover for DP 21-3900A - Part 09154841

    Motor and walking belt assembly diagram

    Motor Cover

    Part #09154841

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

  • Washer for DP 21-3900A - Part 26014100

    Control panel diagram

    Washer

    Part #26014100

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

  • Bolt for DP 21-3900A - Part 22008900

    Bolt

    Part #22008900

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

  • L End Cover for DP 21-3900A - Part 09118600

    Motor and walking belt assembly diagram

    L End Cover

    Part #09118600

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

  • Screw Sm for DP 21-3900A - Part 20018800

    Motor and walking belt assembly diagram

    Screw Sm

    Part #20018800

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

  • Treadbrd/cvr for DP 21-3900A - Part 39319300

    Motor and walking belt assembly diagram

    Treadbrd/cvr

    Part #39319300

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

  • R End Cover for DP 21-3900A - Part 09118500

    Motor and walking belt assembly diagram

    R End Cover

    Part #09118500

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

  • Bolt for DP 21-3900A - Part 22015500

    Motor and walking belt assembly diagram

    Bolt

    Part #22015500

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

  • Lock Nut for DP 21-3900A - Part 25011100

    Lock Nut

    Part #25011100

    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: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor co…

Main causes: damaged walking belt, improper belt tension, bad roller bearing…

Main causes: faulty sensors, wiring failure, bad control console…

Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor…

Main causes: bad control console, wiring failure, bad motor control board…

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…

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 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 time and Difficulty

 45 minutes or less
How to replace a treadmill walking board

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…

Repair time and Difficulty

 30 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 time and Difficulty

 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.…

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