Changing output of WB O2 setup (Autronic)

[Jörgen Karlsson]

Hi,

Here in sweden the M&W controller is used with autronics autotune, I think
that the problem is not as big as it sounds. Since the 0-1v output on the
autronic WB controller is equal to 10-30AFR and the M&W controller has a
10-20AFR range a potentiometer is used to make the number on the display and
the number the autronic ECU sees match.

By the way, how much are the M&W controller in the US?

After looking at the response curve of the canadian unit (FJO inc), I have
found it not to be very suitable. I would rather read the serial output of
the controller and make a Atmel processor send a pwm voltage signal to the
autronic ECU. The serial output has the values in acsii format if I
understood it right. This should be a simple operation in BASCOM-AVR. You
could apply any filtering you need in the program code.

Jörgen Karlsson
Gothenburg, Sweden.


> Hi all, I could use any advice anyone can lend.
>
> I bought an Autronic SMC engine management system.  It has the Autotune
> feature (adjusts AFR based on input from WB controller).  The Autronic
> requires 0-1V input.  There is only one solution, according to
> Autronic, and
> that is their own Autronic controller (at cost over $1000US).
> They say the
> M&W controller is not a good match to the Autronic (AFR not stable).
>
> FJO Inc, has what appears to be a very nice unit.  It is $636, with sensor
> and display.  However, according to their engineer, their unit would not
> work with my Autronic.  He tells me that 0-1 V and 4-5V on the
> analog output
> is reserved for communications with their own ECU, and the AFR is
> shown from
> 1-4 V.

> Now my question is this:  How can I filter, alter, or create a
> new signal to
> reflect the ratio?  The FJO unit has serial output.  Is there any
> way I can
> generate a voltage from the computer suitable for the ECU to
> read?  I mean,
> the laptop will know the AFR.  Is it possible, without a lot of work, to
> create a voltage on the 0-1V scale to be sent to my Autronic?
>
> I have a feeling I need to just bite the bullet and pay the
> $1000, but if I
> can save money, I will surely go for it.
>
> Thanks
> jay
>
> PS> If any other Autronic owners have dealt with this, please let me know.

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