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Hi, I have created a skyline R32 Gts-t (born with rb20det) and put a

Rb25det in it.

I have installed Apexi power fc and it works super.

The only thing that does't work, my rpm in the original

dashboard.

It works fine in the hand controller.

What could be the problem.

Sincerely, René

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Wiring problem only. Must be. I (and many others) have a 25 in a 32 and it just works. I don't know for sure, but maybe, just maybe, the tacho output on the ECU plug is on a different pin between the two. I wouldn't count on that, because you can use RB20 ECUs to run RB25s, so they should be the same. Anyway, check the wiring diagrams, then go fault finding the wiring itself.

Thank you.<BR closure_uid_9l2gko="2311">The wires are from R32 GTS-T.<BR closure_uid_9l2gko="2312">Does anyone know what color it should be to dash rpm?<BR closure_uid_9l2gko="2313">I can measure the pin 7 of Apexi box if there is signal out?<BR closure_uid_9l2gko="2314">and is the same place apexi hand controller gets the signal?

Thank you.<BR closure_uid_9l2gko="2311">The wires are from R32 GTS-T.<BR closure_uid_9l2gko="2312">Does anyone know what color it should be to dash rpm?<BR closure_uid_9l2gko="2313">I can measure the pin 7 of Apexi box if there is signal out?<BR closure_uid_9l2gko="2314">and is the same place apexi hand controller gets the signal?

The power supply comes FROM the dash and ECU simply earths the supply. If you unplug the ECU and turn the ignition on you should see about 5V (from memory) at pin 7 loom side obviously. On the RB20 loom the tacho wire is red with yellow trace/stripe. Not sure if it changes colour though at the loom plug in the passenger footwell.

Cheers

When I put the old box (from rb20) on in works fine.

It is pin 7 on both box ??

There is 5-6v on the cabel, but nothing on the scope...

I think pin 7 is fired , can take the signal from where the hand controller gets it? Or from the engine and run it without the box?

When I put the old box (from rb20) on in works fine.

It is pin 7 on both box ??

There is 5-6v on the cabel, but nothing on the scope...

I think pin 7 is fired , can take the signal from where the hand controller gets it? Or from the engine and run it without the box?

Can you confirm which loom you are using, R33 or stagea?

wiring is from R32 gtst but adapted, Box is from apexi R33 rb25det. Sorry if I have misunderstood something, Goggel translation is not very good for Danish :-)

As you said, it sounds like the Apexi computer has a fault with pin 7. I am not sure of your modifications but if the engine is close to standard I would try a stock R33 ECU. If this is not an option you could try getting the Apexi ECU repaired.

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