Hello guys, having a little problem here. My blue high beam indicator light on the instrument cluster doesn't work. It hasn't worked during the whole 3 years the car has been in the family, but now we'd like to get that fixed. Any ideas where the problem could be?

-Bulb has been changed (no effect)
-Lights work otherwise 100% as they should (I can turn the high beams on and off without problems)
-The lights have been rewired thru a relay system (original wires only give signal to relays which feed the lights with straight-up battery power), but this hasn't had an effect (did this 2 years ago, indicator didn't work even before this)

Can anybody tell me which pin behind the instrument cluster is it that should convey the signal to the indicator? That way I could test if the problem is in the connections inside the instrument cluster.
Or can it be the bulb "base" that is faulty? (the small grey part that the bulb is plugged in before it can be screwed to the cluster, don't know the English name for it.)

I searched but couldn't find a suitable topic. If anybody else has had the same problem please tell me.