Console "E1". Water damage? Found capacitor leg jacked. Replaced still E1

[vestaviascott]

I picked up this exercise bike, an Exterra UB1.7 model and it appears to have a fault in the magnetized resistance/effort circuitry. On these bikes there are typically and Up/Down arrow to increase/descrease the apparent load/effort on the pedals (aka "Resistance" in the mechanical sense).

From the console readings, everything on this bike appears to operate fine except resistance. As soon as one attempts to increase or decrease resistance on the panel, the unit flashes "E1" on the console. From the owners manual (see pic below), this is indicative of one of several issues:

For the E1 troubleshooting issues, I've eliminated issues 2 and 4 and I'm now focused on 1 and 3 (Console or gear motor circuit). Replacing the gear motor with a known good motor has no effect so I moved on to the console and opened it up.

After opening the console I found obvious signs of damage. Even still, perhaps amazingly, I find that the entire functionality of the bike, and the panel readings appear to be fully functional but for the resistance control. Even with the capacitor fully removed, the same functionality is present.

The bottom left corner of the console board appears to have some rust and corrosion on several screws and the 16v 1000mu capacitor had one leg completely out of the socket on the board. I removed the capacitor and did a quick test on it and it appears OK. There is some significant corrosion on the board at this capacitor so I attempted to desolder the plugged holes where this capacitor was and try my best attempt to replace this capacitor in circuit (my solder work there sucks), but I'm still getting the E1 error.

Pics attached if you guys have any ideas for next steps.

The circuit board. The loose capacitor is the top board bottom left:

Rust on the screw holding the voltage regulator just above the 16v 1000mu capacitor:

Reverse shot of the top board. Area of interest is now bottom right over flipped over board:

The "resoldered" pins of the capacitor. To the right of the pins solder is spot where a rusted screw head meets the board when its turned over and secured in its normal position. The board is flipped over here for this picture:

 

[duke37]

Your soldering does look rough.
Remove all the old solder with a solder sucker or fine braid with flux.
Make sure there is no connection between the trace and the adjacent circuit.
Resolder joints with cored, leaded solder using a hot iron with a good sized tip.
Heat the joint and then add solder to it. A couple of seconds should be enough, if it takes longer you are not doing it right.

I have no idea how these things work but suspect that they use electro-magnetism to provide the resistance so would look for broken wires and connections.

 

[vestaviascott]

Heat the joint and then add solder to it. A couple of seconds should be enough, if it takes longer you are not doing it right.

Thanks. I'm never sure when the joint is hot enough because no matter how long I hold the tip on the joint, after removing the iron the solder never seems to melt into the joint. So on this try, I fumbled with trying to melt the solder onto the tip of the iron and let it flow into the socket. It didn't work great at all. I need much more practice soldering obviously. I have my iron on 375 Celsius and my solder is Kester "Kwik Draw" rosin core solder 60% tin and 40% Lead. .050" diam. I'm using the 2nd largest tip in my kit, which is wedge shaped and about 1/8 inch across.

I have no idea how these things work but suspect that they use electro-magnetism to provide the resistance so would look for broken wires and connections.

There is a magnet bracket that sits close to the flywheel. The bracket is hinged at bottom so that it is just 1/8" from the flywheel. At the top of the magnet bracket is where it moves back and forth from 1/8 inch maximum resistance then away from the flywheel at about 1.5 inches (minimum resistance). The mechanism that moves the bracket is a steel cable attached to a 6 volt tension motor. The tension motor is controlled by the Up/Down controls on the console.

 

[vestaviascott]

I understand that the problem here could be my terrible solder job and I will undo that and redo.

I'm using the same capacitor that came out of the circuit on this. I do have a new capacitor but I was reluctant to use it until I could try getting the old one reconnected (and for fear of ruining it with my novice soldering ability).

When I first tested this cap, my test for it was to first probe it on the ohms setting, then on 20volts to see that it gradually lost voltage. It did so, so I presumed its a good cap.

I have a new cap. It it possible/ok to simply dry fit the new cap in place, by bending the leads over the back of the board, then power up the bike to see if the E1 clears? Or does solder need to be present to force the connection bridge between the board and the capacitor pins?

 

[duke37]

Solder runs towards the heat so you should put the solder on the hot joint not the iron. You may need a little on the iron to just wet it and so conduct the heat to the joint. Putiing a blob of solder on the iron and then transferring to the joint does not work.
60% tin and 40% lead is correct. I do not know if 375 Celcius is enough. My iron is not controlled and I just leave it 5 minutes to heat up.
My iron tip is bigger than yours!
You should end up with a nice shiny surface due to surface tension.

You must have a solder connection made with the solder flowed to the two surfaces.

Is the motor energised, up or down?

 

[champagne_charly]

How's c3 next to the triac? One side looks rather dark. Has it burnt or just tarnished?