RPM/Gear & actual road speed

[derb]

If you are good at converting kph to mph...

To access the AC diagnostics:
Hold down the Recirculating & Air Up buttons for 5 seconds. The + - buttons go up and down through the list of "c" codes. The center vent button switches the display between the "c" code and its actual value. Press the Auto button to exit.

Go to 20c.
20c - Vehicle speed in kph, updating only once per second. (real speed, not speed+safety margin as in the speedometer)

I haven't verified the speed with a GPS yet but it does read lower than the speedometer.

[Topless]

If you really want accurate you will need to beg, borrow or steal a GPS. Anything else is loose guesswork.

[Lil bastard]

Originally Posted by derb

If you are good at converting kph to mph...

To access the AC diagnostics:
Hold down the Recirculating & Air Up buttons for 5 seconds. The + - buttons go up and down through the list of "c" codes. The center vent button switches the display between the "c" code and its actual value. Press the Auto button to exit.

Go to 20c.
20c - Vehicle speed in kph, updating only once per second. (real speed, not speed+safety margin as in the speedometer)

I haven't verified the speed with a GPS yet but it does read lower than the speedometer.

Yes, this works. It is actual speed in KPH, not MPH.

To convert KPH to MPH, you use the formula:

KPH / 1.609344 = MPH

But, this only works on cars through the 2000 model year only. These diagnostics cannot be accessed on later cars.