dim dash lights

[brian rachlin]

The dash lights on my 1976 Eldo are very dim when the car is running at night.  The battery and alternator are working fine, I was thinking that possibly the rheostat on the headlight switch might be bad.

Any opinions?

Thank you,

Brian

[denise 20352]

  What happens when you turn the knob?  Does it go from dim to dimmer, or is it just ON or OFF?  Do the lights wink if you wiggle it around?  That is a sign of a bad rheostat.

  It is also possible that some of the bulbs are burned out.

-densie

[brian rachlin]

There is no flickering when you wiggle the knob, and the rheostat does allow to make the lights even dimmer and to turn them off.  It works normally, except that at the brightest position, they are still dim.

Thanks,

Brian

[Mike #19861]

 Often it is the bulbs themselves. Even though they may all work, they tend to silver which decreases their brightness.

 Remove the cluster, and replace all of the bulbs with fresh 194s, and you should have nice bright lights again.

 Mike

[Mick]

Hello Brian.
Your first step is to measure voltage at several points in the circuit: Battery +, Lights switch feed, panel lights bus, and verify there is at least 13V running, ideally 13.8V.
If there is any difference of over 0.5V from point to point, a corroded fuse, fuseholder, connector, grounding, can be the cause.
Old bulbs do get filled up after many years of sucking darkness, to the point where they can not suck any more, and it shows with the deposits inside the glass.
When that happens, the only solution is to replace them.
Mick

[Brian Rachlin]

Thanks for the suggestions!

Brian