No backlight on Official display


#1

I just received the official display I ordered from Pimoroni, followed the instructions and the screen turns on, I can see lxde, and use the touchscreen, but i seems like the backlight is not working. Ive tried different power supplies, using the gpio pins, using a usb cable between the pi and the adapter board. Nothing seems to get the backlight on. Do i have a defective screen, or is there something else I should check


#2

Make absolutely sure the LCD ribbon cable- between the LCD and the driver board- is seated properly.

Right now we haven’t seen this problem before, but this would be my best guess!


#3

Tried reseating it a few times, still no luck. Here are some picture of how it is set up http://imgur.com/a/4xzfF . Could it be a power issue?


#4

It could very easily be a power issue- I notice a yellow cable in your picture; what’s that coming from? Is there an amperage rating on the power supply?

I’m going to measure how much juice the display eats. Would be useful to know, I think!


#5

Ive tried a couple of different power supplies, that one was a 1A. Also tried a 2A one. Ive ordered an official one from Pimoroni. Hopefully that works, otherwise I’m out of ideas.


#6

Worry not! If all else fails we’ll replace your LCD and take that one back for diagnosis.

I’m testing power consumption right now with the possibly not quite accurate meter on my bench supply and seeing a draw of between 700-800mA with nothing but a keyboard plugged in. A really good 1A supply should cut it, but doesn’t leave any headroom for peripherals.

A bad 1A supply, probably not!

Might be worth looking for the little rainbow square of low voltage in the top right corner if you can. It seems to kick in just under 5v and would indicate a power supply struggling to keep up.


#7

I tested it with the official power adapter, and still no luck :( How do I go about sending it back to you.


#8

Drat! Drop our support guys an email and they’ll initiate the process.