My stairmaster 7000pt step is grinding and slipping

Question edited for clarity.

Lots of information here

https://www.google.com/search?q=Stairmaster+7000pt.+Why+don%27t+stairs+rotate

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Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

This can be caused by either a loose chain, a failing chain tensioner or possibly, a failing transmission. You can find some troubleshooting information at the following link.
Search Results

Check the following video out for some troubleshooting steps regarding this issue.

Stairmaster Stepper 7000PT Stepmill Parts Transmission SPORTSMITH net

Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

There are a couple of different belts available for this unit. The following link will take you to the parts available for your model.

Stairmaster Stepper 7000PT Stepmill Parts Transmission SPORTSMITH net

How to Test the Relay Board on Stairmaster 7000PT Stepmill How to Test Relay Board of a Stairmaster Stepmill 7000PT Disconnect power from the machine.
Disconnect the main cable from the relay board J1 terminal. Main cable should remain disconnected for the duration of the relay board tests.
With the Power ON, place a jumper wire across the GND/BLK and RLY/RED test points. (Ensure jumper wire only makes contact with the designated test points.)

• Verify that the Relay LED is lit. Remove jumper wire.

With the Power ON, place jumper wire across the +/WHT and FLD/BRN test points. (Ensure jumper wire only makes contact with the designated test points.)

• Verify that the Field LED is lit. Remove jumper wire.

With the Power ON, place jumper wire across the +/WHT and with the other end touch the ALT/C, FLD/NC, and RES/NO.

• Verify that the Field LED lights.

If any of these jumps fail, replace the relay board and or power supply. Stairmaster Stepmill 7000PT Electronic Testing of Relay Board



The second link will take you to the service manual. Starting on page 13, you will find some more valuable information on the relay board. Last link will take you to a video on how to test the alternator
Video about Performing Jumper Test on Stairmaster Alternator

Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

This could be caused by worn alternator brushes. The following link will take you to a video on testing the alternator. If the alternator checks out, you may be dealing with a faulty display console.

Video about Performing Jumper Test on Stairmaster Alternator

First thing you'll want to do is check the alternator brushes. Here's a link to the different types offered for the Stairmaster 7000PT:


Repair Parts for Stairmaster Equipment Batteries Springs Belts Chains...


If the brushes look like they are in good condition you can also test the relay board. This link will take you to the procedures for checking the relay board:


Stairmaster Stepmill 7000PT Electronic Testing of Relay Board

console could be defective try to diagnose it by entering diagnostic codes from your manual
also check the mechanical parts inside , a hinge rod could have slipped out and has pinned the entire stairs

check inside where power receptacle is sometimes the steps hit the wiring and breaks a wire off therefore no power to the control board
if not that do an alternator check refer to owners manual not hard to do could be diode that needs replacing usually the small electrical component on the exterior of the alternator
last if you have all electrical working the gear reducer gears may be stripped (usually a grinding noise or skipping feeling when this happens ) a rebuilt one or new one can be purchased from glide fitness products in santa ana california for very reasonable price they are good people to deal with also they can assist with trouble shooting
good luck

If you have a Stairmaster Stepmill 7000PT that has an older style console with the red LEDs and you want to upgrade to the newer, console with the blue LCD; the parts necessary for this upgrade include the console and the console cable.

Stairmaster Stepmill 7000PT Console Upgrade
C40 Console Repair Video for Stairmaster Steppers