2003 US model Grand Vitara 4x4 V6 gas with an auto trans.  Going to put 29-30"-ish tires on it and was recently clued into the Yellow Box by Black Robotics in Australia for correcting the speedo/odo.
www.BlackRobotics.com

Ordered one yesterday, but they came back with some questions:

"Before we can ship your Yellow Box we need to know what type of speed sensor your Grand Vitara uses. Does it have a 2-wire inductor type speed sensor, or a 3-wire hall-effect type sensor?

Also we need to know if the speedo system is controlled using a multiplex/bus type system from the ECU, where one wire controls several vehicle systems.

A service manual or a wiring diagram will indicate the type of speed sensor used. And should also list the ECU control over the speedo, the wires going from the ECU to the speedo will be labelled as a "bus" or "bus-shunt" if the bus/multiplex system is used.

If you can find the speedo and the ECU on the wiring diagram see what the wiring looks like between the ECU and speedo. Actually it is probably easiest just to look at the speedo.

See what the speedo connects to; either wired straight to the ECU with nothing in between, or wired to other systems between the ECU and speedo. If there are other systems between the ECU and speedo what are they?"


I...barely understand what they're asking.  I checked and I have 3 wires on the speedo sensor on the transfer case so I know that portion.  However the ECM bit of their question has me stumped.  I've got a Suzuki FSM but it isn't helping much, not very clear on these sort of things.  Anyone know the answers to these questions of theirs?

WhereTF is the ECM anyways?

You say you have a FSM, does that include a wiring diagram? I can look later, I've got to go to work now .

From what I've seen the wire from the VSS goes directly to the speedometer... There is a connector in between though, but no ECM I can send you a pic of this part of the diagram if you give me an email .

Sergi, thanks for the offer but we managed to figure it out.  I started flipping through the FSM page by page and managed to track down the wiring diagrams I needed.  I found the same as you, just one wire connecting the two and nothing special.

Suzukis have always been known for their simplicity and ease of maintenance so I doubted there was anything special going on with the wiring.

Thanks for the help though!