e-licktronic Forum

I finished my NAVA build, but when I power it up I don't have any characters displayed on the LCD. Where would I begin to trouble shoot this issue?

Have you tried adjusting TM3? (LCD contrast)

Yes I've tried adjusting the contrast and it has no effect

Hard to say exactly, first thing I'd try is this.

If you installed the Newhaven LCD, you can remove R694 and in it's place solder a trimmed resistor leg and that should fix it. If that doesn't work you may have bigger problems.

draztik wrote:Yes I've tried adjusting the contrast and it has no effect

Did you remove the plastic from the header pins before soldering? I had left mine on and my LCD had no connection with the plastic on the header pins. I had to de-solder the LCD and remove the plastic, then re-solder in the pins one by one.

draztik wrote:I finished my NAVA build, but when I power it up I don't have any characters displayed on the LCD. Where would I begin to trouble shoot this issue?

Please check traces with multimeter (continuity mode) like this:

http://www.bilder-upload.eu/show.php?fi ... 579780.png

If you don't have a connection between those points you need to solder a wire/ jumper.

Example:

http://www.bilder-upload.eu/show.php?fi ... 015410.jpg

Thanks for the help everyone. I removed R694 as suggested by

metronome wrote:Hard to say exactly, first thing I'd try is this.

If you installed the Newhaven LCD, you can remove R694 and in it's place solder a trimmed resistor leg and that should fix it. If that doesn't work you may have bigger problems.

This solved my problem

draztik wrote:Thanks for the help everyone. I removed R694 as suggested by

metronome wrote:Hard to say exactly, first thing I'd try is this.

If you installed the Newhaven LCD, you can remove R694 and in it's place solder a trimmed resistor leg and that should fix it. If that doesn't work you may have bigger problems.

This solved my problem

That's weird. With 1.2k in R694 the display is more dim, but you should still see characters. Anyway, great you solved it!

draztik wrote:Thanks for the help everyone. I removed R694 as suggested by

metronome wrote:Hard to say exactly, first thing I'd try is this.

If you installed the Newhaven LCD, you can remove R694 and in it's place solder a trimmed resistor leg and that should fix it. If that doesn't work you may have bigger problems.

This solved my problem

Awesome! Glad that helped you.

KlangGenerator wrote:

draztik wrote:Thanks for the help everyone. I removed R694 as suggested by

metronome wrote:Hard to say exactly, first thing I'd try is this.

If you installed the Newhaven LCD, you can remove R694 and in it's place solder a trimmed resistor leg and that should fix it. If that doesn't work you may have bigger problems.

This solved my problem

That's weird. With 1.2k in R694 the display is more dim, but you should still see characters. Anyway, great you solved it!

I can put the 1.2k back in R694 and see what happens. I would like to know 100% this was the issue and not just a mistake by me not adjusting the contrast enough. I'll do some further testing incase anyone has the same problem. I'll let everyone know what I come up with.