speedometer lights

[rmmchl]

i removed the center cluster for temp gauge repair-thought it would be good to check the 2 lights on my speedomter so i removed it also----I tried to turn on speedometer  lights to see if they work and now they won't  come on-does the center cluster have to be hooked up before they work-also----------Does the brown ground wire connect to the thumbknob on the back of the sppedometer brackett??

[waqas]

Yes and yes.

[Jonny B]

Keep in mind that the rheostat that controls the dimming on the lights might also be a bit messed up (corroded - a common issue). You may have to finagle that to get to the "sweet" spot. If that is the case, once you find it, just leave it alone. The bright setting is just about acceptable by most modern standard. There are a number of posts about how to bypass the rheostat if that becomes an issue.

[J. Huber]

Related to what JonnyB just said -- when I recently had my center gauge worked on, I somehow lost the rheostat function. Not sure how but it used to work, "now it don't." The strange thing is, it is now stuck on what I have to believe is the brightest point -- it was never that bright when it worked! I was happily surprised last time I took an evening spin .... so ya lose some, ya win some.

[Allenh]

The brown wires are all battery negative, ground.  each of the instruments has a brown wire attached by the knurled nut to provide the B- for the lamps.  No wire, no lights.  Also, the blue wires can break off the lamp sockets.  I lost one on assembly- wire was on when I inserted the lamp socket, first after dark trip let me know I had a problem.  These are old cars ya know.