Y connector for speedo?

[poorsh2]

Could a Y connector be made so you could install a KPH cluster but still keep your mph odometer up to date?

[suckerface]

I really doubt it. I'm sure that CTScott will chime in with a technical answer, but I have a feeling it'll be a resounding no.

[tk-421]

@suckerface: I don't know about that...

You can change the odometer to read whatever you want now thanks to research made by CTScott:
http://www.yarisworld.com/forums/showthread.php?t=41461

So I'm pretty sure there's a way to switch between between MPH and KPH (which probably involves switching a constant value somewhere in the code or changing it at the moment the "register to db" function is called).

I'm sure CTScott can clear things up for us.

[CTScott]

Unfortunately not, since the cluster is an active CAN bus device with 2 way communication to the ECM.

What you could do is have me reprogram the KPH cluster to your equivalent current mileage. Then, with the KPH cluster you'd continue to increment properly, but just in Km's instead of miles.

[CTScott]

And, in regard to TK's thought about simply changing the Kmh cluster to log in miles instead, unfortunately that code lives within the microcontroller (and at this point I can't do anything with it), so I can just change to data that resides external of it, which is the odometer data.

[tk-421]

That makes a lot of sense.

Is there any chance that a TSR-like program could be written that intercepts the data right before it is written to the log and changes it? I'm sure there's got to be very little memory to play with in there, but maybe a super tiny assembly app could do the trick?

Of course, there's still the issue of starting the app up in the first place...

[CTScott]

Originally Posted by tk-421

That makes a lot of sense.

Is there any chance that a TSR-like program could be written that intercepts the data right before it is written to the log and changes it? I'm sure there's got to be very little memory to play with in there, but maybe a super tiny assembly app could do the trick?

Of course, there's still the issue of starting the app up in the first place...

That would be tricky, as you would need a piggyback PCB to mount in place of the tiny 8 pin surface mount EEPROM. It also wouldn't help with displaying the info, since once the car starts moving the cluster processes the raw data from the tranny sensor, displays the data, and then occasionally sends a backup copy of it out to the EEPROM.

[poorsh2]

Thanks for all the input, It sounded to easy. oh well