As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A SERVICE DOOR CAUTION MESSAGE ON CLIMBOUT. CREW FOLLOWED THE QRH AND RETURNED TO TLH WITHOUT INCIDENT. MAINTENANCE INSPECTED AND FOUND THE SENSOR CAP JAMMED. MAINTENANCE REMOVED AND REPLACED THE PROXIMITY SWITCH CAP. OPERATIONAL CHECKS WERE PERFORMED. AIRCRAFT WAS RELEASED FOR SERVICE.