Like New Nautilus Exercise Bike has Dead Panel

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

Pictures are too poor, there has to be regulator some where on that main board.

I'm taking these with iphone in HDR mode. I'll try again this morning with a lens over the phone to see if that helps. I will also take 4 zoomed quadrant shots of the main board. Coming up!

Really appreciate the help.

[budm]

Re: Like New Nautilus Exercise Bike has Dead Panel

Pictures are too poor, there has to be regulator some where on that main board.

[Curious.George]

Re: Like New Nautilus Exercise Bike has Dead Panel

That DC jack does have a switch. Pin 1 center pin (+red?), pin 2 barrel (-black/white stripe?), pin 3 switched barrel (mystery beige?).

Yes, but what likely role would a switch THERE serve in such a device? (Goal is to have OP think about why "it" would care about whether the power adapter was mechanically attached -- or not!)

[Curious.George]

Re: Like New Nautilus Exercise Bike has Dead Panel

I am trying to locate Voltage regulator IC's and some Voltage test points on that board.
I think I can see one 3-pin regulator.

Photo in post #24. D2 for reversed power protection, C14 on input and C15/C16 on output. (I can't see designator for the actual regulator).

My directions to OP would have him stumble on it within an inch of the wiring harness meeting the PCB as he traced foils...

[budm]

Re: Like New Nautilus Exercise Bike has Dead Panel

Too blurry to me to read anything on the board, see it for your self what you can see in that picture.
I am trying to locate Voltage regulator IC's and some Voltage test points on that board.
I think I can see one 3-pin regulator.

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

Can I see good clear straight shot of the console board?

[budm]

Re: Like New Nautilus Exercise Bike has Dead Panel

Can I see good clear straight shot of the console board?

[Curious.George]

Re: Like New Nautilus Exercise Bike has Dead Panel

First thing I would like to determine is if the board is getting power. To do that, I'm first going to measure the voltage of the red wire (#2) at the top console harness. I believe I should expect from 5-9 volts if everything downstream has proper continuity.

Adopt some convention for referencing signals, pin numbers, connectors, etc. E.g., there are several "#2" pins -- the "10 pin red connector" appears to be the reference frame for your choice of "#2". But, there are other places where you may, eventually, be referencing (connector) pin numbers.

E.g., HD5 and HD6 each have NOTHING in the pin #2 position -- and HD1 has nothing in ANY position!

So, for the test, on the DMM, black lead to ground wire (#5) and red lead to red wire (#2), and I should get a voltage reading when the power adapter is plugged in. All good to start?

Yes, just be careful not to let the probe slip off and potentially short out "something".

As there is nothing (electrically) attached to the red wire (isn't it Red w/white tracer?), there is nothing drawing current from the power adapter. So, there will be no voltage drop along the length of the cable. What you saw AT the adapter should also be present "exactly" at the red connector (assuming you are probing it before connecting to the circuit board).

Once you mate the connector to the PCB, there will be some load on the power supply so you might see a TINY voltage drop at the circuit board end of the wire. This is because wire has resistance and, therefore, current flowing through it (to power the circuit board) causes a potential to be developed across it. "IR loss" (I=current, R=resistance, I*R=volts)

One of the first things you should do is verify the connection of the "ground wire" to the "large expanses of foil" (e.g., that cross-hatched area and anything electrically tied to it) on the circuit board. This will give you a variety of other places where you can make a connection to "ground" (convenience).

Once that test is complete, and assuming I get expected voltage, should I just pull this board and measure from the solder joints on this other side of these wires?

Visually trace the power signal as it transitions ONTO the circuit board. It will be a large-ish trace so relatively easy to follow. See where it goes. Pay particular attention to any devices that it appears to pass THROUGH (i.e., places where the only way for power to continue onto the board is THROUGH that device). Probe the "far side" of those device(s) to verify that power is, in fact, passing through. If not, you need to understand if the device/component has failed (e.g., fuse) and is interfering with power being available for the board or if the device is supposed to intentionally interrupt the flow (e.g., a device used as a "switch"). In the latter case, you'd need to figure out how to "turn on" that switch. Or, if it is there to somehow condition the power (e.g., a voltage regulator).

Goal, here, is to identify the OBVIOUS places where power should flow and verify that it does, in fact, do that.

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

Saturday finally here! So, I've finally got some time to work on this bike to try to figure out what's wrong with it.

First thing I would like to determine is if the board is getting power. To do that, I'm first going to measure the voltage of the red wire (#2) at the top console harness. I believe I should expect from 5-9 volts if everything downstream has proper continuity.

So, for the test, on the DMM, black lead to ground wire (#5) and red lead to red wire (#2), and I should get a voltage reading when the power adapter is plugged in. All good to start?

Once that test is complete, and assuming I get expected voltage, should I just pull this board and measure from the solder joints on this other side of these wires?

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

OK, finally had time to pull the crank, remove the side skirt and undo that cable bundle to trace the wires. Here's a couple of illustrations of the wire traces:

The wires are numbered sequentially in the order they appear in the wire harness in the 2nd pic below from right to left (there are 11 wires going into the harness, -W indicates a white lined wire):



From right to left, you can see there are 10 wires coming into the harness, 3a and 3b are the two gray wires that are spliced in the harness as you can see from the 3rd pic below:



The 3 wire is a splice of the two gray wires are fed into the harness from the power adapter harness and the speed sensor:



Finally, here is where the harness wires attach to the main board in the same order as the harness in pic 2 above:

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

Interesting Budm. That may be what happened to the damn thing. I haven't been able to get away from work for a few days. Hoping to have a chance to run these tests this weekend and get a drawing up.

At this point, I've written off this bike for any profit, HOWEVER, the insights and knowledge I'm gaining from your help will be very helpful in the future as I continue to take in cheap/free failed electronics and try to bring them back to life.

[redwire]

Re: Like New Nautilus Exercise Bike has Dead Panel

That DC jack does have a switch. Pin 1 center pin (+red?), pin 2 barrel (-black/white stripe?), pin 3 switched barrel (mystery beige?).
The mating connector seems to only have two wires (gray, red with white stripe)?

Best to check it with a continuity test.
Most important is knowing the barrel polarity, if it is (-) or (+) on the treadmill.

[budm]

Re: Like New Nautilus Exercise Bike has Dead Panel

Check the resistance between center pin of the DC input jack and the red wire on the red connector: I expect it to show <1 Ohms,.
Check the resistance of the terminal of the red connector that is connected to black wire against the terminal that the white wire is connected to: I expect it to show <1 Ohm.
Notes: AC adapter is not connected to the DC input jack during this test.
BTW, there is strange warning about the AC adapter.

[Curious.George]

Re: Like New Nautilus Exercise Bike has Dead Panel

Sorry guys, been a crazy day at work. Here are some pics of that barrel connector and I'll also draw a wiring schematic from here all the way up to the console:

Interesting. This suggests there may be a switch in the connector (though I can't imagine why -- there are no batteries in the unit, are there?) I.e., the designers decided that there is a need for the circuit to "know" when the wall wart is MECHANICALLY plugged in -- despite the fact that voltage would only be present to the circuit IF it was plugged in!

WITH THE HARNESS UNPLUGGED (i.e., with the "pink" connector's contacts accessible), plug the wall wart into the jack (and into AC). Now, carefully (so you don't accidentally short your probes -- and the power supply! -- together) probe between each pair of wires (there are three pairs: 1+2, 2+3 and 1+3).

You should see the wall wart's output voltage (~9.2V) on at least one of the pairs. These represent the conductors that are directly connected to the center contact and outer sleeve of the wall wart's plug. If the display reads (+) 9.2V, then whichever wire is connected to the positive input of the DMM corresponds to the center contact of the plug. The other DMM lead is on the sleeve of the plug. If the display is -9.2V, then the opposite is true (i.e., the positive lead of the DMM is on the sleeve of the connector)

Make a note of this in your drawing so you know where "ground" and "power" come into the circuit.

Now, with your DMM on "ohms" scale, see if you have continuity between either of the "other" pairs.

For example, if 1+3 showed you the 9.2V (which may appear as -9.2 depending on how your leads happen to be positioned on the contacts) and 2+3 showed "nothing" as did 1+2, then check for continuity between 2+3 and also between 1+2.

Note that if you saw voltage on any of these other pairs, don't bother checking for continuity.

Then, unplug the wall wart -- from the AC and from the wire harness -- and probe all three pairs for continuity.

If there is a mechanical switch in the connector, the act of inserting the wall wart's plug will open (or close) it. The above is trying to identify the presence of a switch and its action.

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

Sorry guys, been a crazy day at work. Here are some pics of that barrel connector and I'll also draw a wiring schematic from here all the way up to the console:

[budm]

Re: Like New Nautilus Exercise Bike has Dead Panel

As you can see in your post # 1 & 11, you show someone else picture (FRP?) of the DC input jack which we cannot see how 3 wires are soldered to the DC input jack, you need to show the pictures of your unit.

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

Sounds good. I'll make a drawing. Thanks for the help.

[Curious.George]

Re: Like New Nautilus Exercise Bike has Dead Panel

So, now that we know how the 3 input power wires turned into 10 (tension motor and speed sensor), is it possible to begin troubleshooting the control panel?

As I said, upthread -- MAKE A DRAWING. Or, do you expect each of use to try to "trace" wires from a dozen different snapshots to try to figure out "what goes where"?

There are TWO conductors on the power connector ("wall wart"). You haven't explained why anyone would WASTE a THIRD wire to attach to a two-wire connector.

If I see a "Blue" wire in ANY photo, can I assume that it is electrically connected to every other instance of a blue wire in ANY other photo? What about Red? Etc.

With the piece of equipment in front of you, you *could* troubleshoot it by running your fingers along a particular wire to see where it goes. Doing that from a bunch of photos is considerably harder -- the wire may not be completely visible, we may not understand the "view" we are being shown, etc.

Even if YOU can trace a single wire, you will find that making a drawing will save you the trouble (and possibility of making a mistake) of having to remember where each wire went. A drawing gives you The Big picture.

[You started this thread stating: "I'm new to electronics troubleshooting but I really want to learn the basics. I feel like its a skill that I really want to invest time to learn." My comments are intended to get you thinking in a more systematic way -- so you will learn to SEE where you need to look for problems.]

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

different model slightly but shows wiring you cant see
https://www.youtube.com/watch?v=3BJzrbIy2RU

Awesome find. Here are some stills I grabbed to show the tension motor which is responsible for 5 of the 10 wires going into the control panel:

[vestaviascott]

Re: Like New Nautilus Exercise Bike has Dead Panel

So, now that we know how the 3 input power wires turned into 10 (tension motor and speed sensor), is it possible to begin troubleshooting the control panel?