LCD stays blank

Kits Audio Hi Fi Projects
1

After using K8095 for quite some time now, I decided to add the optional LCD.

So I removed the LD4, removed the “no lcd” jumper on J8 and attached the recommended LCD.

The LCD backlight works, but absolutely nothing appears on the screen… . I have checked soldering, by checking conituity between each contact point on J10 an another point on the PCB. Tried different positions for RC1 (= contrast?).
No change… So: any further ideas would be appreciated…

Player continues to play fine, and al buttons seem to work OK.

2

Yes, RV1 is the contrast adjustment.
The voltage on pin 3 of J10 should be 0V to get maximum contrast.
Here the measured voltage on the pins of J10 when the power is turned on but song is not playing:
1 = 0V
2 = 4.75V
3 = 0V
4 = 3.3V
5 = 0V
6 = 0V
7 = 0V
8 = 0V
9 = 0V
10 = 0V
11 = 12V (backlight+)
12 = 5.6V (backlight-)

There on the pins 7…10 is varying voltage 0V to 3.3V when the song is playing and if the MP3 file contains song data displayed on the LCD.