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Wed Jan 18, 2012 9:15 am

Hi all,

Anyone know how to wire up a 12 volt VDO tachometer? I have a nice used German one here (0 - 7,000 rpm). Besides the terminals for the dash lighting, I have three terminals marked +12, 1, and - . I'd "guess" that "1" goes to terminal "1" on the coil? "-" might be to ground? "+12" might be a line to 12 volt power??? Hell, I don't know!

Anyway, if you have an VDO tach install instruction sheet, or have one wired up, can you confirm what each terminal should be wired up to? If needed, I could shoot a photo of the backside. Thanks!

Bill

Wed Jan 18, 2012 10:12 am

Don't take my word for it and burn it up but I think "1" is hooked up to negative on the coil, "12" is your 12 volt power source and the the third terminal is prob. the source for your tach. light to come on which would hook up to tail light terminal.......hopefully u get some more opinions.

Wed Jan 18, 2012 11:44 am

1 is the coil connection on other vintage VDO tachometers I have owned and used.

Wed Jan 18, 2012 12:01 pm

Thanks guys! I don't have a coil anywhere near me right now, isn't there a "15" and a "1" (or maybe it is a "-") terminal? So, is the "1" terminal on the tachometer then wired to the "1" or the "15" terminal on the coil? Hopefully someone may still have a old copy of a VDO tach install instruction sheet they can refer to, or better yet, scan and post here showing the wiring... I'm thinking of using this on my '67 Westy in an unobtrusive location somewhere.

Thanks!

Bill

Wed Jan 18, 2012 12:33 pm

on my VDO tach the wire on the coil just goes to the negative side. im sure yours would be the same. however dont quote me because mine is a new one.

HIJACK. on an old VDO tach do you have to use a diode like some of the new ones? i have a diode in mine.

Wed Jan 18, 2012 12:58 pm

durfeec wrote: on my VDO tach the wire on the coil just goes to the negative side. im sure yours would be the same. however dont quote me because mine is a new one.

Although not a VDO tach, I just went out to look... and my 'new' tach is also hooked up to the negative side of the coil.

So, Vote #2 for the negative side of the force Luke. :roll:

Wed Jan 18, 2012 5:03 pm

The '63 wiring diagram shows a "1" on the side that connects to the distributor.
15 for the ignition side.

I checked an NOS 1959 Bosch coil I have next to my desk and it has a 1 and a 15 as the connections.

Wed Jan 18, 2012 10:24 pm

As found in the galley...

Thu Jan 19, 2012 6:51 am

You can go to the VDO website and view/download the diagrams for all their gauge units.

Fred

Thu Jan 19, 2012 7:44 am

Depending which coil you have like a Bosch or aftermarket some are marked with +/-...and some are marked 1 and 15......but "1" = negative, and "15" = positive for the ignition coil.................I would think you just need to run a wire from your gauge from "1" on gauge to the negative/1 terminal on your coil and run the other wire 12+ to your 12v power source, just plug into fuse panel on the accessory terminal the same place your coil wire is plugged into, and your third wire (-) will just go to ground.