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NordicTrack
Treadmill

Model # NTTL18903 Official NordicTrack apex 4100i treadmill

Here are the diagrams and repair parts for Official NordicTrack NTTL18903 apex 4100i 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 187 parts  |
Treadmill Walking Belt Alignment Tool (replaces 161927) 128457

#135

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Treadmill walking belt alignment tool (replaces 161927)

Part #128457

This item is not returnable
$2.49 | 
29% OFF Phone Price : $3.49
In Stock
Treadmill Circuit Breaker, 15-amp (replaces 031103, 127202, 173322) 109382

#55

All parts diagram

Treadmill circuit breaker, 15-amp (replaces 031103, 127202, 173322)

Part #109382

This item is not returnable
$9.39 | 
10% OFF Phone Price : $10.39
In Stock
Treadmill Safety Key Assembly 160695

#82

All parts diagram

Treadmill safety key assembly

Part #160695

This item is not returnable
$5.99
In Stock
Magnet,rnd,m 100498

#107

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Magnet,rnd,m

Part #100498

Replaced by #113842

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Manufacturer substitution
This part replaces 100498. Substitute parts can look different from the original.
This item is not returnable
$2.16
Back Order
Black & Decker Exercise Equipment Reed Switch 157504

#20

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Black & decker exercise equipment reed switch

Part #157504

This item is not returnable
$10.99
In Stock
Exercise Equipment Nut 012179

#77

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Exercise equipment nut

Part #012179

This item is not returnable
$2.16
In Stock
Treadmill Screw 149442

#96

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Treadmill screw

Part #149442

This item is not returnable
$2.16
In Stock
Black & Decker Incline Motor Bolt, 2-in 159986
Black & decker incline motor bolt, 2-in

Part #159986

This item is not returnable
$2.16
In Stock
Frame,lift,i 157507

#17

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Frame,lift,i

Part #157507

$106.99
In Stock
Custom Screw 185445

#16B

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Custom screw

Part #185445

This item is not returnable
$2.16
In Stock

Symptoms for treadmills

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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…

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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…

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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'…

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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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