+1 on do the footwell connectors, but I don't think that's the problem. The left footwell connector carries the signals to the height switch & BECM, so bad connections there only stop the switch working.
More likely is a sensor or driver pack connector issue, so the ECU thinks the car is grounded, and raises the car before going into fault mode. Diags is the first step. Also check the connectors underneath the valve block, and the sensor connectors underneath the car.