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Hi guys,

I've read there is a test point somewhere in the engine bay where the tacho signal appears. Can someone tell me where it is? I have looked everywhere and cannot see a plug where I'd find this signal.

Thanks.

Mike

Ps. I have a Series 2 R33

Edited by mikep

I've bought an SAAS tacho from Autobarn which might be faulty as it didnt read any revs when I had it connected to the ecu line at the back of the dash, which I had to put back together last night for a trip. For quick testing purposes (so I don't have to rip the dash apart again) I thought I'd use the test point in the engine bay, plus 12v and an earth are easily accessible there too.

Mike

I know the rb30s have one in the engine bay blue wire but havent come across it in the other rbs, guess other options take out the ecu from the kickpanel and try from there since thats pretty easy to get to.

Edited by boostn0199

If it is faulty they say I can't have an exchange until they send it away to the distributer who will confirm the fault, and I only bought it Friday night!! I don't even get any illumination when it's connected to power either..

If it didnt work at the ecu pinout its not going to work at a test wire if there is one, since its from the same pinout. I know the rb30s have one in the engine bay, dont know about the others.

It's more about double checking that I didn't have it wired up wrong. I want to do this double checking, if possible, without pulling the dash apart again.

Mike

Yeah sort of mis read what you were saying at first but as I said in my edited post use it from the ecu and try.

Yeah I'll do that if I can't find this mythical test point, I'd prefer the engine bay, just because of easy access to gnd, 12v and (maybe) the test point.

Mike

are you sure you had it connected to the right wire at the back of the dash? might be worth just accessing the wires at the ecu and hooking up to tacho wire there. a quick search should find you a pinout for the ecu wiring.

are you sure you had it connected to the right wire at the back of the dash? might be worth just accessing the wires at the ecu and hooking up to tacho wire there. a quick search should find you a pinout for the ecu wiring.

Yeah I am. I connected up a portable frequency counter which showed a static reading at idle which gradually increased with the revs. It was also the colour code reported on another SAU thread. In the troubleshooting part of the manual it says to connect the gauge to a 12v source and see if the backlight comes on, well it doesn't. Not only that, you can't set the shift light point, the needle does not move off it's peg.

Mike

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