Problems with digital LCD Climate control

HI chaps, I've had a problem whereby half the screen is missing on my LCD in my 98 2.0 Exec Safrane. I bought a replacement unit from a 1995 model but the connections were not quite the same, 2 out of 3 fitted so I connected it up to test. I then hooked up the old one and now, when the unit has power there's a ticking sound from under the windscreen in the dash, it sounds like the motor is sticking, but If I turn the blowers on they do work. I'm concerned that the motor will burn out or something and cause a fire. Any ideas chaps? It never used to do this until I attached the older unit. I've removed power from the battery for a bit to see if I can "reset" anything but that didn't seem to work. I'm not worried about leaving the unit in the car,

A little late but perhaps worth a mention anyway.

The Safrane uses a backlit display which appears to be non-functional when the bulbs have blown. There are 6 or 8 bulbs in total in the rear of the climate control unit. the ones you want are situated nearer the top edge. the bulbs at the botton illuminate the row of function buttons below the screen.

This may not be the issue but worth checking before looking further....

I replaced all mine as a matter of course, the display is now consistent and bright.

I am still looking for advice on how to remove the main dashboard assembly to gain access to the illumination bulbs for the speedometer and the odometer display....anyone got any ideas?

edit: I didn't see the date...