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Dyno with cruise control
- Thread starter bboxer
- Start date
According to the service manual, the permissives to enable cruise control operation are the brake switch, vehicle speed (VSS) and clutch switch. The vehicle speed has to be above 45 km/hr for the cruise control to engage.
The cruise control function has no direct input from the front wheel speed sensors for the ABS / TCS systems. The actual ABS should be inactive if you are not pressing on the brake pedal. Have you disabled the TCS? Since you are on a rear wheel dyno the TCS will be reading the equivalent of a gross amount of rear wheel slip. Also, the 1997 and later TCS gets front wheel speed signals out of the ABS for the purpose of calculating yaw. However, I expect that the yaw error may be less of an issue than the wheel slip error.
The cruise control function has no direct input from the front wheel speed sensors for the ABS / TCS systems. The actual ABS should be inactive if you are not pressing on the brake pedal. Have you disabled the TCS? Since you are on a rear wheel dyno the TCS will be reading the equivalent of a gross amount of rear wheel slip. Also, the 1997 and later TCS gets front wheel speed signals out of the ABS for the purpose of calculating yaw. However, I expect that the yaw error may be less of an issue than the wheel slip error.
When you put the car on the dyno and pressed down on the throttle pedal to start picking up wheel speed did you get the TCS engaging - trying to cut engine speed? If the TCS was on that should have happened because it would be interpreting 0 speed on the front wheels and no speed on the back as massive wheel spin. If not, and you were able to bring the vehicle up to the test speed you were looking for then the TCS must have been already off. If the cruise control would not engage then I expect something else was amiss. Do you know that your cruise control actually operates?
If you were never able to get the test started then the TCS might have been your problem. The TCS will allow some wheel spin to facilitate quick take off; but, at some point it says enough and starts to engage. Depending on the year, a 5-7% difference in wheel diameter due to tire mismatch will generate TCS operation.
If you were never able to get the test started then the TCS might have been your problem. The TCS will allow some wheel spin to facilitate quick take off; but, at some point it says enough and starts to engage. Depending on the year, a 5-7% difference in wheel diameter due to tire mismatch will generate TCS operation.
Thanks again. My car is one of the original CT car. It has been fine with smog checks for decades until one O2 sensor was changed. Monitors have been giving me trouble for over 4 years! I was not at the shop on Friday when the car was put on the dyno. i will be there tomorrow. BTW, on some cars it is not enough to disconnect the TCS with the switch, it requires a disconnect at the box. Is that the case with the NSX?.
Thankfully the NSX is old enough that the designers still trusted people to know how to drive.
The button will shut off the system.Similar threads
