KT-LCD5 display controller campatability.

Hi everyone, hope you can help me. I have a SW900 display that has bit the biscuit. I need a new display, but I need it yesterday. I have found a KT-LCD5 display in town and I'm wondering if it will only work on KT controllers. My cheap Ebay kit, 48v 1000w rear direct drive hub, has a LY-48v-1000w controller. I really can't wait 3-4 weeks. Will I fry the display or my controller if I hook them up? Thanks for reading.

ebikeruss said:

Will I fry the display or my controller if I hook them up?

Click to expand...

I'd think you're question would be whether it would work or not, but as far as frying it, good chance not. If you look at the pin out order of the KT and the SW900, they both use battery voltage; controller on/off; ground; data; data. So it probably wouldn't "fry".

But, it probably won't work either, in case that matters.

OK, thanks for your reply. I guess I will order one and wait the required time. Thanks for saving me some money, but more importantly, for educating me.

ebikeruss said:

OK, thanks for your reply. I guess I will order one and wait the required time. Thanks for saving me some money, but more importantly, for educating me.

Click to expand...

Sadly there are no standards in DIY ebike world or compatibility between brands. I'm even surprised that the pin outs are the same, but maybe both companies use harnesses that come off the same assembly line.

Yes, standards would be nice. I'm really going to show my ignorance now. How could I bypass the display to keep riding until one arrives?

The LCD displays are stand alone, so if they have the same pinout (and many do) they power up but cannot talk to the controller.

Many controllers have a default powerup where you can run without a display. You get one PAS level and the throttle works.

So yes, the original poster can investigate that. On a five pin LCD connector, you have these five pins. They're in the same order on the flat JST plug for my LCD3 and SW900 connectors. Don't know about yours. Of you have a Julet waterproof, it's different.
-Battery Power
-Controller start
-Data out
-Data in
-Ground

When you start the display, it supplies battery power to the controller start and then uses the two data lines. To jumper a controller to run without display, you jumper the Battery power lead on the connector to the controller start lead. KT controllers come with a jumper plug to do this so you can run without the display.

Now this is battery power, 36V to 52V and if you connect it to any lead but controller start you will either fry a data lead of fry the connector ground, So you have to be sure. What's wrong with the SW900? No screen?

Thanks for the info. My SW900 is giving fluctuating speed readings, I can be riding about 30 kmh and it will bounce all over the place from 0 to 14 to 0 to 25 back to 0 etc. also it won't let me throttle at all when in PAS 1or 2 but will in 3. It worked in all PAS settings for two years. I don't have PAS connected or even installed. And forget about the ODO.

ebikeruss said:

Thanks for the info. My SW900 is giving fluctuating speed readings, I can be riding about 30 kmh and it will bounce all over the place from 0 to 14 to 0 to 25 back to 0 etc. also it won't let me throttle at all when in PAS 1or 2 but will in 3. It worked in all PAS settings for two years. I don't have PAS connected or even installed. And forget about the ODO.

Click to expand...

Are you using an external speed sensor or the motor magnets/halls for speed?

On PAS, if you set P05 for 5 PAS levels instead of 3, do you get the same result? (3, 4, 5 work?)

I'm using motor magnets/hall sensors, "46", for speed. I will try the 5 PAS level setting to see if that helps. If not I already purchased a KT controller and the KT-LCD5 display. Thanks for your help.