Siemens 840-D PCU50 backlight

Hi, Does anyone know if the backlight in a PCU-50 with Windows NT has a user changeable backlight, or is it something that I have to send in for service?

I can barely see the screen so I know that it is working, it's just that the backlight has gone out. Thanks in advance.

Yes it's possible

Have seen recently a Siemens PCU50 / OP12 where a service engineer has replaced the Cold Cathode lamp and added a seperate inverter with 12DV input. This was being run from a mains plug pack. I recently replaced the plug pack with a 24VD-12VDC (500mA) regulator (used extensively in trucks to reduce voltage for other auto accessories). Altogether a good fix, certainly more cost effective than buy replacement Operator panel from Siemens.