As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TYS - A/C WAS EN ROUTE FROM ORD TO PNS WHEN A WARNING INDICATION OF AIR-GROUND FAIL MESSAGE APPEARED ON THE ICIAS. THE CREW DIVERTED TO TYS WHERE MAINTENANCE REMOVED AND REPLACED BOTH LT MLG WOW PROX SENSORS IAW EMB 145XR AMM 32-36-01. OPS CHECK GOOD AND WAS RELEASED. S/N OF PROX SWITCHES OFF-1169 AND 1114.