Defektes Kombiinstrument? Mehrere Fehler vorhanden

[Erich]

da faellt mir gerade was ein, sowas hatten wir vor 11 Jahren an einem E32 750, Kollege hat hier die kalten Loetstellen nachgeloetet, Problem beseitigt, hat extra noch etwas von Gehaeuse rausbrechen muessen um an die Kontakte zu kommen  http://www.bimmerboard.com/forums/posts/569942/
Problembeschreibung damals:
there are 3 bulbs on the grey cluster for then ilumination of the speedometer, RPM meter, the fuel and temp indication. These are in series. When slapping on the dashboard the lights on temp indicator came on. We switched the cpl. bulb with socket with the middle one, fault moved. Turned out to be a slightly burned bulb holder, the bulb was o.k.
The RPM indicator as well as the econometer moved sometimes not or erratically. Soldering of some points solved that (cold solderings).