cruise control on jdm nsx

[rtbm]

car is jdm ...1991 spec, fitted with cruise..all works fine except in cant get the car to set and hold any speed above 70 mph....use the "resume" and the car speed to over take but wont set and hold any speed above 70mph, it will set below this ...am i missing something guys????

[Mike_L]

I believe all JDM vehicles with cruise control have a limiter fitted. My JDM prelude I had a few years back was limited to 100kph (62.5mph) which is the Japanese national maxium speed equivalent to our 70mph. (are you sure yours is as high as 70?). The way you describe the behaviour is exactly as mine was.

You will also have a 180kph (112) maximum speed limiter fitted if you havn't found that already.

There are several companies that specialize in removing these limiters although not NSX specialists of course. I think it is in the engine management system, anyone else know for sure?

[rtbm]

sounds about right...many thanks

[markc]

rtbm,

My import NSX does the same as yours so it's not a fault, just a feature.

Fortunately the 180kph limiter was removed along with the fitment of the kph to mph convertor. I believe this is a simple signal "pulse" convertor.

Thinking about it....

The speed signal for the cruise control must be a differant one to the speedometer as this has been modified so that the speedometer reads in MPH instead of KPH. I suspect the speedometer is driven by signal provided from the gearbox.

If this same modified signal fed the cruise control it should work at speeds upto 112mph??

I may have dig out and pore over the wiring diagrams as some stage (probably during the winter) to see if the above is true and a simple wiring re-route will allow cruise control upto 112mph rather than 112kph :)

Mark