interior clock trouble, please help

[baz coupe]

i while ago i noticed that my interior clock has started de-laminating and the numbers starting to disappear. i recently purchased another clock off ebay and tried to install it. i followed a workshop manual so got the clock no problem. i noticed that on the clocks connector there was a wire coming from the live feed and straight onto the bulb itself, definitely someones repair job. i installed the new clock without this wire and when the lights turn on the clock numbers disappear, i tried putting the wire back in but still the numbers disappear when the lights go on. both the new and old clock now have this problem so its not the clocks, maybe a grounding issue?

please help

regards harry

[Cocacolakidd]

On the clock back side there is a 4 pin male socket. Negative - is to lower right, Positive + is lower Left, Positive + for light is Upper Right. If you can jumper these connections with a 9 volt battery while the clock is out, to check it's function, then it is truly a back wiring problem - There should not be an extra wire besides the 4 prong wiring. The light bulb is to the left of the 4 prong socket and is a twist out assembly if you need to check it's function.