Technical rev counter wiring [Punto mk1 TD 70]

[MatteoIT]

Hello, I had to replace the instruments cluster (the entry level one with no rev counter and just the high temperature warning light) because the tachometer was not working.
I got one with the rev counter and now I would like to make it working.
Anyone can tell me how to wire it? Many thanks :wave:

 

[simon_16vpunto]

Have you installed it already, it should work.

People who had 55/60s models when the cars were newer and more popular, used to upgrade to sx clocks with rev counters, plug and play.

 

[flisko]

its not plug&play, you need to wire rev counter
and you need to put in temp sensor which was in sx

https://www.fiatforum.com/punto-mk1-guides/77439-how-wire-up-rev-counter-mk1-punto-s.html
https://www.fiatforum.com/punto-mk1-guides/77517-how-fit-sporting-sx-temp-gauge-into-s-mk1.html

 

[simon_16vpunto]

My bad, sorry

 

[MatteoIT]

flisko I have read that guide, but I guess it's for the petrol model, not for the diesel I have.
I already have the blue wire in the right pin in the dash, I have checked the wire from the sensor on the flywheel to the pin in the dash, but I have checked that I haven't any tension in the sensor itself.
According to Haynes manual the sensor is also wired to the EGR control unit either with the blue wire and the white/green wire.
I suppose the W/G wire would be the tension to the sensor, so maybe I have a faulty EGR control unit?
I have also checked the resistence of the sensor and it correctly is 700 ohm.
Any input much appreciated

 

[flisko]

dont know about diesel

 

[MatteoIT]

None has ever fitted a rev counter into a diesel model?

 

[flisko]

maybe diesel already has it wired, maybe it is plug&play, get another speedo and try it, we will investigate after that

 

[MatteoIT]

Yes, I can confirm that diesel has already it wiered (I checked this), but it isn't plug&play.
I took the car to a car-electrician who checked the speedo on a special diagnostic tool, so I am sure the speedo is OK. We also checked the resistance across the engine speed sensor and it is 700 ohm, as required by the specifications.
Something isn't correct but we cannot spot it out