Lcd illuminates but no text is being displayed. On the back of the i2c interface module I turned the screw in both directions, however the contrast was not adjusted. The screw is now stripped. Would it be possible to add a potentiometer to control the brightness?
pi@raspberrypi:~ $ uname -a
Linux raspberrypi 4.4.27+ #2 armv6l GNU/Linux
pi@raspberrypi:~ $ i2cdetect -l
i2c-1 i2c 20804000.i2c I2C adapter
pi@raspberrypi:~ $ vcgencmd version
Copyright (c) 2012 Broadcom
version faf071dd4885c5ac1a89483d35a5326e7f69495f (clean) (release)
installed python-smbus and i2c-tools
enabled i2c in raspi-config
any suggestions on what else to troubleshoot?