Hi,

everything is in the title really. I've got a Chinese aftermarket Rev Counter that I want to fit to my 2F, but I don't know which wire to get the coil signal from. There must be something behind the dash that I can use. The other wires are ignition positive, ground and lights, so they are easy. I've looked for a 'W' terminal on the alternator, but there isn't one, and I've looked at the wiring on the coil, but it is labelled '1' and '15'. Any ideas?

I've also fitted front foglights to the cutouts in the plastic spoiler, but can I power them via the same switch as the rear foglight. Is it a two-position switch only?

Any help greatly appreciated.

Robin

Hi Robin.

How many pulses per revolution is your rev counter expecting?

Could you post a link to the rev counter you purchased?

Hi,

this is the rev counter:

https://www.ebay.co.uk/itm/166838283986

It can be adjusted for 4/5/6/8 cylinder engines, etc. What I need to know is if there is an easy place to connect the green (Coil +ve) wire.

Thanks,

Robin

I made it work!

I connected power and earth under the bonnet, sat the rev counter next to the coil and tried the green wire on terminal 15 with no result then on terminal 1 and it showed tickover with the engine running. Terminal 1 is connected to the thicker guage black wire on the coil plug, so now I need to figure out if this wire goes anywhere near the dash...

Robin

As you've found out, it's the negative terminal of the coil that you need.

Neatest place to connect is probably at the ignition control module. This wire won't exist inside the car. Only between the ignition control unit and the coil negative.

This type of ignition control module is (was) available with an output pin designated to drive a tacho, but I'm not sure if that's analog voltage or pulsed.

For you front fog lights, best not to add them to existing switch due to current (amps) required.

Suggest a fused relay with the relay coil connected to the switch and the relay fed via a fuse from battery.

Just to mention, adding OEM rev-counter clocks is fairly straightforward. The FAQ also identifies a lot of the wiring that you'll need either way

https://www.clubpolo.co.uk/topic/31883-mark3-clocks-faq/

Thanks to all. I will update as soon as I have time to get things connected.

Robin