How to check temp gauge?

[Bimmerfanatik]

Ok, I tried throwing another VDO temp gauge I had into my Motometer cluster, and it ain't workin. Now Jordan said they should be interchangable. Giving him the obvious earned benefit of the doubt, how do I test a temp gauge out of the cluster to make sure it's working? Send a constant signal or something I assume?

[Jordan]

the center terminal is ground. give 6volts at one of the other 2 and see what happens. Should bring it to half way.