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Discussion Starter #1
Previously I had read a post by andy42uk, link shown below, which details how to modify an R33 GTS speedo to read in mph.

http://www.gtr.co.uk/forum/upload/showthread.php?t=52998&highlight=speedo

I promised myself that I would have a go with it, especially since my speedo recently packed up. Initially I dismantled the dash and bypassed the kph to mph converter and hey presto the speedo jumped into life, so the converter was the cause of the problem. Anyways, now the speedo was reading in kph. BTW I have a 320kph nismo speedo in an R33 GTR. I also have a PFC with controller and noticed that the speed signal was now reading correct values, whereas previously it would read the corresponding value in kph for the true mph, 80kph for 50mph.

I went through the procedure as detailed by Andy but unfortunately the numbers were way out. With J2 linked and PESL cut it was not possible to get the speedo to read low enough and also the signal to the PFC was now reading low.

So I connected up my scope to the speedo input and output signals and monitored them whilst driving at various speeds recording samples at 40 and 50mph as measured on my Road Angel to determine the wave type and frequencies in and out.

I then removed the speedo head from the car and connected it up in the house. It was powered by a bench supply and a similar signal was input to the head. The signal was set to the same as measured at 50mph and then I had a play with the jumpers.

I found that on my Nismo head the PESL should remain linked and J2 should be left open circuit. When J2 was linked the signal out from the head was reduced by a factor of 2, so the ECU and HiCAS too, I would presume would get a low speed reading by a factor of 2.

Anyway all that was needed to get the speedo correctly aligned was to adjust the links 1 to 9 as detailed in Andy's document.

Bear in mind I have a Nismo head which I think removes the standard speed limiter, plus the PFC also removes the speed limiter so that is not a factor for me.

I reckon it would be fairly straightforward to modify the standard head to do the same thing but would need to get hold of 1 to do so.

Cheers
Paul
 

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Discussion Starter #2
Unfortunately the odometer seems to be clocking up in km so will have to have another look at it and see if I can figure it out.
 

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Now got the odometer functioning correctly too so it's 100%, not that anyone seems remotely interested in getting their speedo sorted so that the HICAS functions correctly, as I haven't had a single reply :bawling:

Anyway if anyone does want to have their speedo function correctly in a JDM R33 GTR without a converter that will bugger up the HICAS you might want to drop me a line :sadwavey:
 

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anyone else have success doing this?
 
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