Fix Your NordicTrack Exercise Bike

Introduction: Fix Your NordicTrack Exercise Bike

About: Software Developer, like to work with electronics, embedded systems, robots etc.

The other night I was riding my Nordictrack exercise bike and all of a sudden the display quit and the tension on the peddles went slack. The wife has been on me for quite some time to start exercising as I sit behind the computer the major part of the day.

So I decided to take the thing apart and see If I could trouble-shoot what was causing the control and display not to function. I will get into showing you the tear down shots later.

Right off of the bat I thought, cool if the controller is shot I could replace it with a micro-controller solution.

This would be a cool project.

But then reality set in and I realized that this project would take some time and I am currently working on some other micro-controller projects. So back to tearing the thing down and see if I could fix the darn thing.

The display has two sets of connectors coming out of it. I had no clue to what they were connected to. So I decided I had to tear the plastic off the bike and take a look at how the bike was wired.

Grabbed the multimeter and some tools. Stripped the bike down to the frame and started taking a peek how this bike works.

Lets take a look at the key sections of the bike.

Step 1: AC Adapter

We will start at the front of the bike. Notice the ac adapter, 12 volts, 1 amp DC adapter.

Step 2: The Pedal Assembly

A bit further back, The pedal assembly, Notice the Hall Effect sensor and the magnet mounted to the pedal assembly.

The Hall Effect sensor is used to count the number of wheel rotations and calculate things like speed and distance traveled. Along with the hall effect sensor and the weighted wheel potentiometer, calories burned can be calculated.

Step 3: Rear Weighted Wheel

At the rear is the business end of the exercise bike, there is a weighted wheel with a tension adjuster and a motor.

In a minute we will look at how the motor and wheel works.

Step 4: Motor Assembly

Lets take a closer look at the motor assembly.

On the motor we have a lever and a gear wheel no unlike a RC servo motor. So this motor my be controlled like an RC servo motor? maybe, lets troubleshoot some more.

So we flip the motor over and notice how the motor is wired:

The motor has two wires connected, a yellow wire and a blue wire, no this motor is not an RC servo, it is just a DC motor.

Also on the motor control casing there is a label.
On the label it indicates “6V tension motor P/N 241949″

I did some web searching and found that many exercise bike use this same motor.

But I could not find any specifications on the motor. Just a few posts where other people have had some issues and one article on a vague description on how to test the motor by applying some current to the motor to see if the motor gear turned or not.

I flipped the motor to the other side and had a look:

Interesting, There is a 5000 ohm potentiometer on attached to the gear of the motor.

This would mean that when the motor is adjusted to increase the tension of the skid closer to the motor the resistance would increase and likewise when the motor reduced the tension against the wheel the resistance would decrease.

At least that is what I guessed. Lets do some testing.

So I installed the motor back into the exercise bike and put some batteries together for some testing. I applied some voltage to the yellow and blue wires and sure enough the motor started to turn to move the skid closer to the wheel. Just like a servo though there is a stop and you have to be careful not to keep the motor running against the stop.

So then the question is if I reversed the wiring on the motor would the motor reverse direction and turn pull the skip away from the wheel.

I tried it and sure enough the motor changed direction and moved the skid away from the wheel.

I then attached my ohm meter to two of the terminals of the potentiometer and ran the motor forward and backward and the ohm meter read from 0 – 477 K ohms.

The potentiometer readings along with the hall effect sensor are used to calculate calories burned, speed and distance traveled.

I traced the wires back from all connections to the 10 pin wire connector and found out which wires applied power to the display and controller. I also noted where all of the wires from the potentiometer and halls effects sensor came into the wire harness.

Step 5: The Display/Controller

It is time to take a look at the controller/display.

I removed the connectors and display unit from the exercise bike and took it to my work bench.

I opened up the display/control unit and took a peek inside, not a good sign, other than a few capacitors there were no discrete parts, just a bunch of chips.

So I disconnected the keypad and speakers and the iphone dock connectors and applied power to the unit. Instant current overload on the adjustable power supply.

I tried to check a few connections but not much else could be tested. It appears to be a chip issue. There were no burn marks on the pcb traces.

So it looked like the controller was fried.I looked on line and a new controller was over $300.00. No freaking way was I going to pay that much for a replacement controller.

So I did some thinking and came up with a quick and dirty way to get the exercise bike working for around $15.00. Really all I needed was a way to increase and decrease the wheel tension on the exercise bike. I really do not need the fancy data that comes off the bike for the time being.

I could get the bike working and then when I had some time I could come up with a replacement controller using an inexpensive micro-controller solution with a LCD display.

Step 6: The Fix

Did a bit of web searching and drew up a wiring diagram, after a quick trip to radio shack I started to put together a workable solution.

Here is the wiring diagram I came up with:

I picked up a DPDT switch, a DC adapter voltage connector and a momentary push button and a project case that I had laying around on my desk and some wiring.

After wiring up the new controller box I mounted the box to the exercise bike and connected the yellow and blue wires to the new control box:

Notice I connected the output leads to the wire connector using some female jumper connectors. That way when I come up with a micro-controller solution it will be an easy fix to use the existing wire connector.
If you decide to wire up one of you own, you may have to swap the yellow and blue wires in order to have the DPDT switch increase the tension when the switch is pressed in the forward position and pressed rearward to decrease the tension.

There you have it, a working quick and dirty exercise controller. Now I can keep my wife off of my back and get back to my other micro-controller projects.

Enjoy

3 People Made This Project!

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47 Discussions

0
RaK6
RaK6

8 months ago

OK.
Stand corrected to a reply sent me from earlier. I have now fixed mine just by replacing the chip that controls the tension motor. They were correct in saying the chip is a BD6210. It is U3 on the main board. I ordered it, and received a BD6210F-E2 as in image attached. Small SOP chip. My tension motor is now working. No need for a mod, as this was easier to do. Plus you get tension feedback from the motor as to what position it is in. Compared to the mod. So if you suspect the motor is not working in yours. Order the chip. I do have extras if anyone needs one. Order 2 if you are not sure the motor is bad or not. Or you will cook a new chip. So to have an extra. They are very cheap anyways. Throw away prices. Or to be better safe. Order the new motor, and chip. Chips is about a buck anyways. If you want a couple chips, I will send 2 with postage for $5 bucks. Now back to using it more and more. Thanks guys for the help!

BD6210F-E2.jpg
0
techsoman
techsoman

Reply 6 weeks ago

Hi Rak6 I have nordictruck elliptical e 4.0 I plugged wrong adapter i saw one IC burned MU1 as in picture is it same IC as you mentioned in post please let me know

20200731_212949.jpg
0
techsoman
techsoman

Reply 6 weeks ago

Sorry its UM1

0
the_felipeal
the_felipeal

Reply 5 months ago

Do you still have spare ones to sell?

0
RaK6
RaK6

Reply 5 months ago

Yes.
Have a few of them. I can send one in a letter envelope. $5 seem ok?

0
RaK6
RaK6

Reply 5 months ago

Also if you decide to want one or 2 or more. I suggest 2 in case of an accident in soldering.
I can do 2 for like 7 bucks. Send payment to paypal. Account chipmaster86@hotmail.com or you can mail me direct if need be, and discuss address and more. thanks Much.
Also my webiste notebooksquad.com has my mail info. Notebooksquad@gmail.com But that is not part of my paypal account. only my chipmaster86 email is. thanks Bud! ---Ray

0
RaK6
RaK6

Reply 3 months ago

Also we have now fixed 3 of these tension motor issues with this one chip.

0
Ben2515
Ben2515

Reply 3 months ago

Thank you RaK6! I was given the bike and changing the resistance didn't activate that small motor... ordered the chip specified ($12 with shipping) and soldered it on for a full fix...chip didn't look burnt but I figured I would try it before I did this switch option. Glad I did!

0
drsm121998
drsm121998

3 months ago on Introduction

I need to replace the electric cord AND the port on the inside of the bike that receives the plug as they got damaged.(see picture). I can't find the part #'s for the inside port for the plug and the exterior electric cord.
I have the NordicTrack GX 5.0 Pro Recumbent bike Model: NTEX04911.0
I can't reach NordicTrack to order the parts, and need help. If anyone can help me with where to order these parts, and the name & part number I would GREATLY appreciate any help. Thank you everyone! :)

brokenbikecord.jpg
0
drsm121998
drsm121998

Reply 3 months ago

Ok I will take a picture. I have to get help to take the pedals off so I can get a good picture. You are so helpful! I really appreciate your help!!👍

0
drsm121998
drsm121998

3 months ago

Hi everyone, I have a Nordictrack GX 5.0 Pro recumbant bike. The screen on the console is not displaying the time or distance. Those LED numbers aren't fully forming the actual numbers so I can't read the time or distance. I took off the cover above the front wheel and cant see the reed switch, as the manual said to reset that. Am I missing something here? I need to be able to read the top line on the display to see the time & distance but it's just not displaying just that info correctly. Can anyone help?
Appreciate any help!
Thank-you so much.

0
RaK6
RaK6

Reply 3 months ago

Also. The process for changing this is similar to this video.
https://www.youtube.com/watch?v=4JFZkBOV5eU
This is not your model. But follows the same procedure. Or at least close to it.
I doubt they actually sell the socket by itself.
Many techs actually will use an old broken laptop socket, or PS2 sockets, and it can be replaced with those if you are good in soldering electrical wires.
As seen in link:
https://www.ebay.com/itm/NEW-DC-Power-Jack-Socket-Charge-In-Port-Motherboard-for-Sony-PS2-PlayStation-2/223064297920?epid=12021891240&hash=item33efab11c0:g:YzgAAOSw5UVa0Eue

0
RaK6
RaK6

Reply 3 months ago

Can you send a pic of the board area? This bike actually uses the same display as the Norditrack Eleptical. And I suspect actually the LCD connector should be removed and plugged back in. As it is not making contact well. The reed switch has nothing to do with display missing characters. Now if you see the board itself, just look for the long flat ribbon cable. As in the pic attached. Unlock it by lifting the black outside long tab. Lift out the ribbon, look for any liquid damage or debris on it, and then put it back in. You should be done then and it will work. I suspect it became somewhat unseated.

FETGJKZJ9JFY1QZ.LARGE.jpg
0
drsm121998
drsm121998

Reply 3 months ago

Thank you so much! I will do this and see if this works! I really appreciate your help. Will update on how this goes.....

0
drsm121998
drsm121998

Reply 3 months ago

Now having parts problems for the plug & port...Just posted another question if you could help.

0
vin_ct
vin_ct

10 months ago

In one of the comments
below someone was asking for a source to purchase replacement plastic gears for
the ICON resistance motor. It seems that failure of one of the gears is the
common fault. Has anyone found a source?


Thanks,


Vin

0
MladenS4
MladenS4

Reply 6 months ago

Problem is in potentiometer, it gives false readings to servo controller so motor spins until gears broke.

0
AgentLuke
AgentLuke

Question 1 year ago on Step 5

Great article. We plugged the wrong power adapter in and fried this part on the board. It appears nothing else is damaged, though, I cannot see the other side of the board. If I tried to solder this fried connection down, might that fix my problem?

I already ordered a motor for
The gearbox and sent it back. That’s when I discovered it was getting no power and investigated the board.

I AM QUITE NAIVE...but I cannot pay $260 for a board for a NordicTrack gx 4.0 that I paid $175 for 8 years ago.

Could you please tell me exactly what pieces to order and from where and I will try to construct what you have made? It looks like a great solution to me.

I hope you have time to help. I’ll send you a gift card of some sort :-). Thanks for any help you can give. I’ve read your article 4 times. Radio shack left our town 4 or 5 years ago, unfortunately. I don’t have anyone to ask here in Topeka, Kansas.

Ps. I also don’t have any soldering experience except for a wireless PC Card that I wasn’t able to fix.

D1F6A644-62F8-44D3-8F7B-6B5976F1527C.jpeg0260E003-E5D1-4A53-A2BB-654157789C27.jpegFA10B9BC-3005-4879-AF2E-36C14601452F.jpeg