Open collector tacho output

[Theo]

Hello

I am going to be fitting my Dash 2 (standalone, no DL) to my Nissan powered BMW and have most things figured out with the exception of the tachometer. The Nissan ECU outputs an open collector signal whereas (as I understand) the Dash 2 needs a 5 or 12v square wave input - would anyone be able to suggest the best way of converting?

Many thanks

Theo

[pault]

Assuming that there isn't anything else to the tachometer output. All you need is a pull up resistor to either 5V or 12V. The value depends on the tachometer output capability and the input current requirements of the dash 2. Unfortunately I don't know either of these.

Paul

[Support]

Hi Theo,

Please try connecting a 1000 ohm resistor to the signal wire and 5v.

Kind regards,
Support (K)

[Theo]

Thanks for the replies, after a little more research I found someone else trying to do the same thing and they had success with a 10k resistor so I will try this first and move on to a 1k if the result isn't satisfactory.

[Theo]

10k pull up resistor to 5v worked nicely, thanks again for the replies.