12/71 dash light dimmer switch ?

[timsz]

On my switch there is one wire going to it. It looks like the other wire, as in pic, is broke off. I see switches on ebay that have two wires going to it. Should that other wire be connected to the switch? On the wiring diagram I see two wires going to dimmer. one is red, with white stripe. Other is red with blue stripe. Is that the switch on the wiring diagram? Thank you very much.

[grannyknot]

Hard to imagine a situation where the instrument lights on a Z would be too bright to the point they would need to be dimmed.

My dimmer was the same with a broken off wire so I connected both to the same terminal and bypassed the dimmer and still can hardly see the instruments at night.

Chris

[Namerow]

Not sure what wiring diagram you're looking at.  None of the versions I've seen make a specific call-out of the wiring colours at the dimmer rheostat.  It seems obvious that the wire on the right (in the wiring diagram) is RL, but the diagram leaves it for you to guess at the colour of the wire on the left.

Anyway, the wiring on the rheostat from my '70 is intact.  Both wires are RL.  In your #1 photo, you have one wire intact, located at the 3:00 o'clock position.  It has a male spade connector at its loose end.  The one that's snapped off belongs on the terminal located at the 5:00 o'clock position.  This one has a female spade connector at the loose end, c/w the usual clear plastic shield.  Both wires are the same length.

If you're going to try to fix your dimmer rather than jump it, you'll need to clean the wiper and resistor coil with De-Oxit.  Then put a light smear of dieletric grease on the rubbing surface of the resistor coil.  Finish with a tiny drop of light oil in the control shaft bushing and you should be good to go.  Mine works ok, except for an annoying dead spot over the 30% - 50% part of the control range.

[timsz]

Here's the diagrams.

[z boy mn]

I did what Grannyknot did, as my rheostat knob got loose and the dash lights flickered a lot or were just out. So, I just bypassed it tying together the two wires on the switch (so I didn't modify the original wiring harness) and I'm certainly not blinded by the gauges on the dash in any way at night. I did try to remove it and repair it at first, but it was so hard to get to that I just about decided to pull the whole dash...and then came to my senses. Bypassing definitely was the right option for me.

[ktm]

As everyone has stated, just connecting the two wires together is your best bet..  Between the 40 year old wire, 40 year old connectors, 40 year old fuse box, and 40 year old dimmer switch, you have a lot of corrosion related resistance drop.  If you are game, you can wire up a relay to the dash lights to help and then replace the dimmer with a new one, but its far simpler to just connect the wires.