As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHX - air turnback - 5/31/01 - FLT 49 - on climbout at 10000 ft the left aft entry door light illuminated. the door handle was observed not fully closed and had a small air leak (L4 door); the aircraft returned to PHX making an uneventful landing. in PHX the L4 door was rigged IAW AMM 52-11-13 and operational and pressurization checks were good; no further discrepancies.