Adding hours to new Faria tach

[Viper driver]

Replaced the tach on my 04 SN196, needed to add 800 hours to make it correct.

i made this signal generator and it actually works. Now I just have to wait 33 days for it to be correct.

Thought someone here might find this interesting. Used a 12V battery from my lawn mower with a trickle charger, a few capacitors, resistors, and an IC. Generates a signal which my tach interprets to be idle RPM.

[Viper driver]

stole the schematic, below.

[scottb7]

Well I have not done so on that particular gauge. I had to correct a new hour meter on my old boat and simply used below pictured directly to two wires for hour meter portion.

[MLA]

Why? The true engine/boat hours are stored by the ECM. Its common knowledge that the faria hour gauge will reset to zero under a low voltage event.

[scottb7]

I think above is true only on gateway systems. I am unsure what is true of 2004. But you can tell by the pic on the back of the gauge in post 2 that this gauge is not going onto helmsman gateway system, right?