S12S / S-LCD3 problem

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
This is what happens when I turn it on, and the battery is around 39.2V:
This should show a cutout, unfortunately, the display is too dim to see anything:

edit: actually I have an idea. When I tried to make the PAS work I noticed that the signal voltage was quite low (around 4.1V) even with a full battery. What if the DC-DC converter in the controller is faulty? Or maybe is not faulty only it was meant to be used with a 48V battery?
 
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JuicyBike

Trade Member
Jan 26, 2009
1,671
527
Derbyshire
Agree with Awol above: try setting C11 to "1"
You may have an older controller not able to provide all the signals that this display would like. Setting C11 to 1 eliminates some assumptions made by the LCD. See page 32 of the manual. Good luck to you!
 

awol

Esteemed Pedelecer
Sep 4, 2013
1,216
374
I know you've said it worked ok at the beginning but I would also double check the 5 coloured wires from the LCD3 plug match the same colours wire going into the controller on the socket.
 

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
Agree with Awol above: try setting C11 to "1"
You may have an older controller not able to provide all the signals that this display would like. Setting C11 to 1 eliminates some assumptions made by the LCD. See page 32 of the manual. Good luck to you!
I did try that today (C11=1) nothing changed. (maybe the wattage wasn't shown, but it was very hard to see the LCD).
I started today with the battery @39.4V and came home with 38.8V. The frequency of the cutouts seems to increase, but it is only a feeling, very hard to prove.
 

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
I know you've said it worked ok at the beginning but I would also double check the 5 coloured wires from the LCD3 plug match the same colours wire going into the controller on the socket.
Checked them now, the colour coding is okay.
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
Can you do the following test?
discharge the battery to 36V. Then switch on the bike.
If the bike works OK then the LCD3's automatic 24/36/48 voltage detection mechanism does not function correctly.
 

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
Can you do the following test?
discharge the battery to 36V. Then switch on the bike.
If the bike works OK then the LCD3's automatic 24/36/48 voltage detection mechanism does not function correctly.
The LCD shows my battery full at all times (41.3-38.8V). Why do you recommend 36V?
 

trex

Esteemed Pedelecer
May 15, 2011
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2,671
in your video, the LCD detects 36V correctly in the first 2-3 seconds then dimmed out, ie it seems to identify your battery as 48V.
That could be the result of the 5V regulator inside the controller gone wrong after a few seconds, but more likely that the LCD thinks your voltage is much higher than 36V.
 

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
in your video, the LCD detects 36V correctly in the first 2-3 seconds then dimmed out, ie it seems to identify your battery as 48V.
It is quite dim, but still it shows my battery full. I haven't seen it showing my battery anything but full, apart from the first few moments after a boot.
 

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
I could only find an electric stove for the discharge and it is pretty slow. But it means I could check what happens at 38.2V. The display is barely visible, and when I am trying to change settings it cuts out. Now that is really strange. By morning I guess it will be discharged to about 36V.

edit: still I don't understand why you said that it is the fault of the display and not the controller.
 
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Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
Update: battery is @37.2V and everything looks perfect. I have never seen the display so bright. Only one small detail bothers me: the display shows the battery full, and changing the P5 value hasn't corrected it. Managed to install a PAS. I will give it a good go today.
 

JuicyBike

Trade Member
Jan 26, 2009
1,671
527
Derbyshire
Update: battery is @37.2V and everything looks perfect. I have never seen the display so bright. Only one small detail bothers me: the display shows the battery full, and changing the P5 value hasn't corrected it. Managed to install a PAS. I will give it a good go today.
Well that's good news. I'm sure you've already checked you have a 36V (41.5V) charger, but just in case...
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
Update: battery is @37.2V and everything looks perfect. I have never seen the display so bright. Only one small detail bothers me: the display shows the battery full, and changing the P5 value hasn't corrected it. Managed to install a PAS. I will give it a good go today.
that's good and bad. Good: you've now have a working bike. Bad: it seems to confirm that either the 5V regulator or the LCD is wrong. Can you check the 5V line to see if the voltage moves withing the first 3 seconds after switching on?
 

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
that's good and bad. Good: you've now have a working bike. Bad: it seems to confirm that either the 5V regulator or the LCD is wrong. Can you check the 5V line to see if the voltage moves withing the first 3 seconds after switching on?
Could you elaborate, please?
Now, that the battery is below 38V, everything looks perfect. I ended the day with the battery @35.1V. I can travel at about 38km/h with around 250 watts (plus me pedaling), that is hugely impressive. The PAS is awesome. The whole thing is a little bit better than I've dreamed of. This is excellent fun!

Back to topic. The signal voltage is the same 4.11-4.13V at all times, no matter how charged the battery is. Now with the battery @35.1V I checked what happens at startup, and there is a very short moment when the meter shows 4.45V, but it is too short to give it any meaning, I think.

Now I am charging the battery to max, and we'll see what happens.
 

Golyo

Finding my (electric) wheels
Oct 31, 2015
24
0
45
Budapest
These two videos show the display after boot up with the battery just over and just under 38V.
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
Could you elaborate, please?
.
the LCD works on 5V. It measures the battery voltage with an internal divider - it's difficult to make the voltage drop just for the LCD, that's the bad news. You should ask the supplier for a replacement next time you buy something from them.