As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED THAT DURING CLIMB RECEIVED TOO LOW TERRAIN WARNINGS AT 4,000 FT AND ELECTED TO RETURN TO CMH FOR MAINTENANCE. DURING DESCENT RECEIVED DON'T SINK, TERRAIN, SINK RATE, PULL-UP CONTINUOUSLY. THE AIRCRAFT LANDED IN CMH WITHOUT INCIDENT. MAINTENANCE FOUND THAT WITH RADIO ALTIMETER 1 IN COMMAND THE RADIO ALTIMETER READINGS WOULD DIFFER. THE NR 1 RADIO ALTIMETER WAS REPLACED AND AN EGPWS/WINDSHEAR TEST WAS PERFORMED WITH NO DEFECTS NOTED.