Speed sensor on different instrument clusters

Hello folks

I was wondering if there are different speed sensors to the different kind of instrument clusters??
I have an Tokyo imported GTO where the speedo only shows 180 km/h and I managed to get hold of an american cluster that has miles and km/h showing, but when I tried changing them, the american one will only read up to around 30 mp/h even though I drive much faster, so I changed back to the original one and then it shows the normal speed again, so I was wondering if there is any difference in the speed sensors??
Or does any of you have a guess what else it can be??

The USA ones I’m sure have a slightly different gear ratio so I’m guessing their sender unit will be different.
If you want it to read mph instead you can get a unit that you splice into the wires and it converts to mph.
Very easy to do.

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so your running a jap import with an american speedo cluster…

You’ll need a delimter/convertor chip to change the KMH TO MPH you cant just swap speedo clusters and hope it works.

The convertor chip wires straight into the gearbox speed sensor wiring, once this is done then you only need to change the graphics on the speedo to a mph speedo, all easily avaialable on the net, costs for both the chip and speedo around £80 - £90 for both.

Ugh, that is not excactly what I wanted… Kind off, but I would like to use an american cluster in mine with the original dials that it has, but I just wondered how and what was the trick with the gearbox speed sensor and how to make it work… Dont want to change any graphic or anything on the cluster itself :slight_smile:

Back in the day when mine was imported, when it was SVA’d all they do is what a converter chip on the back of the Speedo cluster , cut the cable to the ecu to delimit it, then stick a MPH sticker over the KPH dials before sticking it on a rolling road to see how accurate it was.

Remember reading somewhere on the web. Those different options (eur/jdm/us) for speedo are controlled by a combination of jumpers & components on the speedo board. Like on the pic circled in red. The jumper J1 (before the caps in the right bottom corner) allegely has someth do do with the us spec.

Again, the guy who posted that was doing a bit diferent conversion (to convert jdm into eur spec 280kmh dial) so the pic shows configuration for that.

He said he got that info from the 3si forum - worth having a search in there…

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So am I getting this right, you have a JDM GTO, and have purchased a Speedo cluster from a USDM supplied vehicle ? so the original speedo in the car reads in Kilometres per Hour up to 180 Kph and the speedo cluster you have purchased reads in Miles per hour up to 160Mph.

I assume you want a speedo that reads in MPH is that all correct so far ?

Best regards

Yes sir… I would of course prefer a 100% euro speedometer cluster with only km/h but I have never seen them so the US version was the closest thing as it has both mp/h and km/h showing… I would just like to know what components are necessary to get it working correctly as the speedometer is only fed by the sensor in the gearbox.

Sidenote, we use km/h here where I am and my car has been delimited from the gentleman in Tokyo whom I purchased it from, it just is a bit annoying not having a clue how fast one goes after the speedo hits 180 km/h


Vince is spot on with regard to it being possible to modify the speedo PCB

The first thing I would say is that as far as I am aware the US 160mph Cluster should work (I am happy to be corrected on that), however in my limited experience the speedos do suffer from dry joints on the PCB, there can also be an issue if the 4 screws that retain the speedo to the cluster body are not tight as it can prevent a good connection to the PCB. In the photo the screws are badly ringed in yellow

If tightening the four screws does not improve the situation then it may be worth checking for dry solder joints on the USDM Speedo.

However I would say your best course of action to achieve your ultimate aim would be as follows :

It is possible to convert your original JDM speedo PCB to read up to 260 KPH and then fit a replacement Dial.

I have done the conversion to my JDM Speedo (I purchased a used one to see if the procedure worked before modifying my own) which was fairly straight forward as long as you are happy using a soldering iron. I did not change the dial on my JDM one as I am in the UK and I wanted my speedo to read up to 180 MPH so I just changed the KMH to MPH on the Existing dial. Photo of the Practice one follows

Once the JDM speedo has been converted replacing the Dial with a Lockwood 260 KPH dial would give you the end result you want. I have included a link to the Lockwood site for the dials https://lockwoodinternational.co.uk/product/gto-kmh-dial-part-no-c620/

If you want to go the JDM conversion route let me know and I will find the photo’s that show the components to be removed and the Jumpers that need to be altered

Hope this helps

Best Regards


Afterthought Lockwood also do a 280 KPH Dial link below




Hi johan, the american cluster is from a twin turbo? Coz i need to change the face of mine from only miles to kilometers and miles.

I have a problem with the speedometer at a point of time it strikes up and down for nothing, maybe the speed sensor is being the fault, is it better to buy an original one or an aftermarket one?
Thanks in advance

When I tried the us cluster in my JDM GTO then it did the excact same thing… The speedo needle just bounced when driving, and worked perfect when switching back to the original cluster again