[quote=“hrg”]I turned on the printer for the first time with printhead disconnected. LCD didn’t light up.
I switched power off and checked connections power supply - main board - display. Seemed to be ok.
Power on again: LCD still blank. Red LEDs on end switches light up, green LD14 on main board too.
Flat cable is ok (checked with ohmmeter).
Then I removed the LCd/SD card reader from the printer and connected it with the flat cable. Now the LCD lights up after about 3 sec., without text, blinking about every second.
There is no problem with the reset buttons: LCD button checked with ohmmeter, button on main board disconnected.
Supply voltage: 15.05 V
What else can I do?[/quote]
I had the same problem.
LCD stayed blank and black when I plugged the printer in for the first time. Checked all connectors on main board. All OK.
Then unplugged all connectors except flat cable and power supply. LCD still bank and black. No use in adjusting contrast.
Disassembled LCD/card reader and reassembled. Now the LCD lights up without text, blinking about every second. Disassembled the LCD/card reader again and plugged the LCD into the reader without spacers and connected the flat cable. Plugging the printer now, the LCD lights up with steady light, but no text. Turning the contrast and voila: The display shows the expected “ERR MINTEMP” screen!
Obviously the spacers are too long (or the pins too short). Will shorten spacers.
Thanks for directing me to identify the problem!