Have a new customer with this unit. Tried calibrating height and was able to calibrate. Even then, with forks on ground, display showing forks at 86" drives slow, have a wrench on display, no codes. Checked history and last code was 389, tilt error. Could not calibrate. A couple of things, where is height getting its input, can you run a test? Need some HELLLLPPP.

Thanks in advance