TSDZ2 controller troubleshooting

[cargoferret]

I've been gifted a 48V TSDZ2 for a cargo bike conversion and boy has it been a journey to no avail so far. Looking for advise on next steps.

The previous owner installed the latest OSF and provided an allegedly working 850C display with OSF and broken SW102.

I bought and installed a new SW102 (according to the wiki linked below) and disassembled and rebuilt the sloppy clutch and shaft assembly (breaking and then replacing the torque sensor ring in the process.)

I powered it up with a new battery, but didn't get any response when attempting to turn on the SW102 display. After probing with a multimeter I found the following voltages on the 8 pin motor control cable:
GND: 0 (was referencing ground)
Vin: ~20 mv
P+ (battery): 52.1 V
UARR TX: ~20 mv
UART RX: ~20 mv
Brake: ~400 mv
5V: ~400 mv
Throttle: ~20 mv
I gave the mv readings in case someone knows what that might indicate.

I've read that the Vin for the screen should be the same as battery voltage when the screen is "enabled". I'm not sure if that means when you've turned on the display or if the display is enabled some other way. Since it got no response on either SW102 or 850C, I perhaps stupidly connected motor P+ to Vin of the 850C and connected GND to GND. I got the screen to power on at least, but since UART was not connected, nothing was going to happen. I tried the same for SW102 with no effect. Now I can also get no response from the 850C either.

So I'm guessing that the motor controller is fried? I'm hesitant to order a new one without further advise though - I've sunk so much time and money into this motor and not sure it's worth it. But my inner fixer and tinkerer insists I repair and reuse. So can someone confirm, is this behavior consistent with a stuffed motor controller? There really is very little good documentation on the electronics (im a mechatronic engineer and expect full state diagrams and detailed pin outs)

Links
Tsdz2 and sw102 connection wiki:

Wire SW102 to TSDZ2

Contribute to OpenSourceEBike/TSDZ2_wiki development by creating an account on GitHub.

github.com

 

[docw009]

Displays only need battery voltage and ground to power up. The display raises Vin from 0 volt to 52V as soon as it powers up. This tells the controller to turn on. It's badly named here. Vin means Vin to the controller. Should have been called Start as it is an output from the display,

I would say you have the wrong wiring for the display if it did not turn on until you applied power to what you thought was the Vin pin. Try it again (unconnected to display) and see which pin goes to 52V when the display turns on. Then see where you wired that pin to the controller. Hopefully, not wired to a low voltage controller pin.

 

[cargoferret]

Displays only need battery voltage and ground to power up. The display raises Vin from 0 volt to 52V as soon as it powers up. This tells the controller to turn on. It's badly named here. Vin means Vin to the controller. Should have been called Start as it is an output from the display,

I would say you have the wrong wiring for the display if it did not turn on until you applied power to what you thought was the Vin pin. Try it again (unconnected to display) and see which pin goes to 52V when the display turns on. Then see where you wired that pin to the controller. Hopefully, not wired to a low voltage controller pin.

Ahh that clarifies so much, I should have guessed that. I tried the steps you indicated, but alas it seems it's too late - neither display powers up. I'm guessing I've fried them both.

I used the wire colors from this post:
'Post in thread 'TSDZ2 OSF for all displays, VLCD5-VLCD6-XH18, LCD3, 860C-850C-SW102.' TSDZ2 OSF for all displays, VLCD5-VLCD6-XH18, LCD3, 860C-850C-SW102.

So next steps are to source a new display... In the meantime is there a way to know if the controller is also done for? As noted originally, the output values don't seem correct, but perhaps they are only meant to be driven high once Vin == V battery? If so, maybe connecting V battery and Vin then probing the 5v and other lines could at least tell if it's online? Potentially stupid idea- this thing is a black box to me at this point

 

[docw009]

Controllers are not expensive, but you might need to learn how to install the OSF. We have two TSDZ2 installs, ridden daily, but we wouldn't ride them with the stock firmware. Too hard to pedal for us seniors. The VLCD5 runs stock with OSF, but it doesn't have a lot of features. I am happy with it, but it doesn't show wattage or voltage. I suppose that if it did show wattage, many owners would get mad at how little shows up..

Google AI says an OSF controller will run without the display. That requires applying battery power to the Vin input, One pedal assist level should work. If the OSF allowed throttle, that should work, THis ia actually a procedure that works with many discrete controllers for hubmotors, and also the older uart based bafang mid drives. I have found it works with the latter, and also with all of my hubmotor controllers. Have not tried it on my TSDZ2/OSF. Just make sure you are using the right color wires on the 8 pin cable from the TSDZ2.





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[cargoferret]

After trawling the OSF forums throughout this debacle, I have become enamored with the benefits - so I'd definitely be installing the OSF on any new controller. Still about $100 which for me is rough (I bought a $300 LiFePO4 battery, I'm on the very high end of the cost sensitivity spectrum).

Reading around it seems like running without a display is widely thought to be possible - although I could fine no confirmation. I'll try it perhaps tomorrow- it's hard when I can only test it on the bike and I need that bike to ferry my child around daily!

Would you happen to know anything about the throttle protocal? I've had a hard time finding out by reading around. I have alot of old 5V PWM throttles, and could hook one up to tide me over if I could figure out if 5V PWM would work as a control signal for the TSDZ2.

Thanks for all your input, it's actually invaluable to me.

 

[docw009]

Again, triple check the pinout before you do it, If you put 48V on the wrong wire of a working controller, that black box is gone.

The throttle connection is three pins,
5V power
Throttle Signal
Ground

The throttle is a 3 pin IC, with power, signal, and ground. Packaged with the IC is a Hall sensor which looks at the magnetic field from a circular magnet in the throttle, Most throttle circuits respond with a signal between 1.4 and 4.3 volts. The input has to be lower than the 5V.

Picture of typical thumb throttle.