1994 Hilux Rev counter issue / questions

[Hiluxplug]

Hi everyone, first time posting in here!

 

My issue is to do with the rev counter in my 1994 3L Hilux. When I bought the truck, neither the speedo, odometer, trip nor rev counter worked, no life at all (the fuel gauge also but that's for another thread). I had the whole instrument cluster looked at by a guy who works on speedos ect locally and was told I was best off replacing it. So that is what I did.

 

I got a new complete cluster unit from eBay and installed it today, to my delight the speedo, odometer, and trip now work. However, the rev counter still does not. It does show some life however, when I turn the truck on the needle jumps slightly which is more than my old one ever did. This is where my question really starts.

 

When the new cluster arrived, the needle for the speedo had fallen off, so I took it apart to place it back on. I had also at this time taken apart my old cluster to see if I could find out why it had stopped working. This is where I noticed that on each of the rev counters there are different numbers just out of view under the plastic when they are assembled. On my old cluster, the rev counter reads " 18.5 pulses " Pulses is in Japanese but I translated it. Whereas, on my new cluster this number is " 7 pulses ". I should also add that I think the new cluster came from the 2.4L Turbo spec as it has the check engine light which ive only seen on the Turbo cars before(?)

 

I have attached photos of the old cluster front and rear, as well as the pulses numeration I mentioned. And of the new cluster in the same manner. I have done some research into what pulses are in this context and it seems its to do with the way the rev counter is given the information from the engine(?)

 

So basically im wondering if the new rev counter labeled with the different (less than half) pulse count is incompatible with my 3L non-Turbo engine and if so, is there any way I can make it compatible?

 

Also, the new cluster has this little black box on the circuit board, my old one did not, does anyone know what this is? (Pictured in the last images)

Image 1: Old cluster

Image 2: New cluster

Image 3: Old rev counter with the 18.5 pulses writing

Image 4 and 5: Unidentified black box from the new clusters circuit board

Image 6: NEW cluster circuit board

Image 7: OLD cluster circuit board

 

Edited October 10, 2022 by Hiluxplug
Photos went in the wrong order, fixed the order of them in the post