Tool for setting twin axle ride height please.

[e39_touring]

INPA is a good tool for performing this calibration. I think you have something else going on with your system.

When you say 'Each corner is showing a massive variation in the numbers', what do you mean by that? If your sensors are OK but out of calibration, each time you hook up INPA, you should see similar results at each wheel that you saw before (+ or - a few mm due to temp variation, etc.). They should also move smoothly when you jack up or push down on each corner (or raise/lower by activating within INPA).

You probably already know this, but note that you're not trying to achieve the 707/709 numbers on the sensor readings in INPA. You do the manual measurement, and take the difference between your measured # and the 707/709 #. Enter that number in INPA as an adjustment, and that's your calibration. Reset the fault light, and then key the ignition and re-measure the height manually. Your manual measurement should now be at or close to 707/709, and you don't care what numbers INPA is showing as it's a relative measurement at that point.

Also, what code(s) are stored when you get the SLI light?