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Three Switches on 5 Speed

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I would like to get my reverse lights working on my '72 240Z. The wiring harness on the car has two connections, but the transmission, a wide ratio 5 speed, has three switches. The connections on the switches are all mangled, (by PO)so I need to find out which ones I need to replace, to get my reverse lights working. I have searched this and all other applicable forums on this site and can find no information regarding the purpose of these three switches. I read about some truck transmissions having a 5th gear switch presumably for cruse control.



Are the two connections on the harness for a neutral safety switch, and a reverse light switch?

What are the three switches (front, middle, and rear)on the transmission for?


I hope the attached picture will be helpful.




Danpost-2470-017631500 1300810575_thumb.jpg

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The switches just complete a circuit when they are in use. Connect an ohm-meter to each switch, the one that completes the circuit when the transmission is in reverse is your reverse switch. It's a good idea to do this anyway to make sure the wires aren't broken (looks like you have one broken already) and the switch moves far enough to complete the circuit.


I think that you're right on the other two, neutral and top gear. The same method applies.

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  • 2 weeks later...
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  • 5 weeks later...

one of the switches, if i remember correctly is an upshift switch



Can anyone elaborate on this? I recently bought a "5 speed" that has 3 switches like this, and my 260Z only has 2 connections. I only wired the reverse light switch.


After the swap, upon driving the car, I could not locate the 5th gear at all in the shift pattern. Is there some wiring I need to do with all 3 switches to get the transmission to be able to shift into 5th, or did I get ripped off with a 4 speed?


First post by the way, really excited to become a member of this community!

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The switches don't have anything to do with the trans going in to gear. I know that the early 240Zs had to have the shifter opening enlarged, but don't know about the later years or the 260Z. Are you sure that the shift lever is not hitting the edge of the opening?


I've only heard of three switches on the 5 speeds, so three on a 4 speed would be new knowledge, for me anyway.

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  • 8 months later...

Some of the Z cars had the "top gear" switch to activate/de-activate vacuum advance. In lieu of a switch when I went to a 5 speed that had no provision, I wired in a toggle on the console, and switched it "on" manually. I saw insignificant changes to the way the car operated. It was probably an "econo-enviro" device, not detectable from the driver's seat. Eventually I eliminated the switch.


Some 5-speeds have one, or all of these:


1 ) Reverse switch.


2 ) neutral switch (perhaps for cruise control cut off) I never investigated the use of this switch.


3 ) Top gear switch.

Edited by cygnusx1
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