vehicle speed sensor modification

[Leon Bezuidenhout]

A question to the technical experts

My Lx470 is a Japanese import and therefore the cruise control limit is set at 110 km/h (i.e. the cruise control works 100% at speeds below 110km/h, but cannot be activated above 110 km/hy - by Japanese law).

To overcome this problem some owners install a "chip" on the speed sensor input wire to the main ECU. This chip remaps the speed input so that the ECU "thinks" the vehicle is moving slower that it actually does, and cruise control can therefore be used at speeds higher than 110km/h.

The speed sensor input signal to the ecu is downstream of the odometer/speedometer so this stays as is.

My question/concern is whether this speed input to the ECU control any other critical functions e.g. traction control, abs, etc and if it will change the way these systems work.

 

[hoser]

I am almost certain VSC, traction control, Adaptive Variable Suspension and transmission shift points relies on information from the speed sensor.

I would try contacting Unichip. I know their chips can eliminate the overall top speed limiters, perhaps it can disable the cruise control speed limit too.

 

[Leon Bezuidenhout]

I believe the unichip will work in exactly the same manner, I.e. remap the speed input to ecu. So will not address my potential concern.

 

[hoser]

Are we are talking about the same Unichip? Other than that, I think it'll be tough to find a work around since the cruise control, control is integrated into the main ECM. It was separate on the 80 series.

 

[Leon Bezuidenhout]

Not sure if we talk about same unichip, but this is how most (all?) piggyback chips work: it takes the inputs from all sensors on car, modify the reading and then send it to the ecu.

 

[NMuzj100]

I wonder if there is something simple like a dip switch setting for JDM vs the rest of the world.

 

[wildsmith]

Didn't see any dip switches in my engine/box ECU when I had it in bits recently unfortunately. How about replacing the ECU with one from a breakers? Make sure you get a master key with it though so you can program your keys into the ECU.

 

[Deanoddg]

A question to the technical experts

My Lx470 is a Japanese import and therefore the cruise control limit is set at 110 km/h (i.e. the cruise control works 100% at speeds below 110km/h, but cannot be activated above 110 km/hy - by Japanese law).

To overcome this problem some owners install a "chip" on the speed sensor input wire to the main ECU. This chip remaps the speed input so that the ECU "thinks" the vehicle is moving slower that it actually does, and cruise control can therefore be used at speeds higher than 110km/h.

The speed sensor input signal to the ecu is downstream of the odometer/speedometer so this stays as is.

My question/concern is whether this speed input to the ECU control any other critical functions e.g. traction control, abs, etc and if it will change the way these systems work.

Hi did you ever get this resolved?