RPM/tach signal wire

[Mattty]

Hi,

Just wondering if anybody knew which wire I can tap into to get rpm signal? Tried putting my multimeter on a few wires on the back of the speedo but couldn't find the right one.A wire as close to the instrument cluster as possible would be ideal.

Edit: Its a 1997 940 2.3 turbo

Cheers

[Clan]

Originally Posted by Mattty

Hi,

Just wondering if anybody knew which wire I can tap into to get rpm signal? Tried putting my multimeter on a few wires on the back of the speedo but couldn't find the right one.A wire as close to the instrument cluster as possible would be ideal.

Cheers

It should be the red and white striped wire , what year and model ?

[Laird Scooby]

Originally Posted by Mattty

Hi,

Just wondering if anybody knew which wire I can tap into to get rpm signal? Tried putting my multimeter on a few wires on the back of the speedo but couldn't find the right one.A wire as close to the instrument cluster as possible would be ideal.

Cheers

Petrol or diseasel?

[Mattty]

Originally Posted by Clan

It should be the red and white striped wire , what year and model ?

Sorry forgot to mention. Its a 940 2.3 1997

[Mattty]

Originally Posted by Laird Scooby

Petrol or diseasel?

Petrol 2.3 turbo 940 1997

[Laird Scooby]

Like Clan said earlier, should be a red/white wire, back of the rev counter should be a terminal you can either undo a screw and use a ring crimp on it or it might be a male spade so use a femal spade, if memory serves should be marked with a "T" - for "Tacho".

It begs the question, why do you need to pick up an RPM feed?

[bob12]

Same colour as 745 vdo on a small Lucar spade .... not much change in basics even if it is a different oem cluster manufacturer. Bob

[Mattty]

Originally Posted by Laird Scooby

Like Clan said earlier, should be a red/white wire, back of the rev counter should be a terminal you can either undo a screw and use a ring crimp on it or it might be a male spade so use a femal spade, if memory serves should be marked with a "T" - for "Tacho".

It begs the question, why do you need to pick up an RPM feed?

I was trying to fit a sequential shift light that I've bought. Its just simply a 12V and ground wire, and a single wire for the RPM signal. I did put my multimeter on a spade connector at the back of the cluster that had a voltage change when I revved it a bit, but it went from about 0.5V AC to about 1v. I connected it to that but then reread the instructions and it said it needs an rpm signal of between 3-20v so I figured I'd just chosen the wrong one, and came here for advice. Is this the spade terminal you're referring to? I think it had a white/purple wire attached to it on a spade terminal.

[Mattty]

Found it, it was as you both said, the red/white wire on one of the plugs going into the back of the cluster. I just removed some sheathing and spliced into it. Voltage ranged from around 4v-15v as I revved it a bit.

Cheers Clan and Scooby

[Laird Scooby]

Glad you're all sorted!