Practically these modules are used to restore the debimetri worn: they are a sort of signal amplifier. In fact, with the time the debimetri (being a hot-wire) subject to wear, and these circuitini serve to restore the correct value of the voltage that would be provided by new!
To calibrate them properly serves for? the use of a computer shop for diagnosis and adjust the trimmer so that the theoretical value and actual value of the match! Them you could do with a multimeter, but only on condition that you know already? a priori, the correct value of voltage that should provide new...
There are both petrol engines and diesel, but usually are not really cheap so thanks to admin for giving us the pattern for them...