I'm not sure on the 2012, but some years have the SeeLevel system as standard. IF your display is in exact percentages, then you have the SeeLevel. Pull the display panel and check the wiring for shorts. If there are none there, you need to remove the fixed panel on the passenger side in front of the rear wheels. There will be screws on the front and rear edges. It's not heavy, but easier handled by two people. Check the wiring on the sensor strips. It's also possible you have a bad sensor strip.
2017 Phaeton 40IH XSH Maroon Coral - Power Glide Chassis with IFS
Previously '15 Tiffin Allegro RED 38QRA and '06 Itasca Sunrise 35A
'16 Jeep JKU Wrangler Sahara or '08 Honda Goldwing