A while a go I discussed a Ward problem when all my door locks seem to quick because off an after market alarm. My alarm person switch back the alarm system to stock and I disconnected the negative terminal black for a half hour . lock works on doors.
What I did discover is the trunk lock will Lock with key but will not shut the doors and gas cap.
The car is a 1992 300-E M103 engine with 48,000 original miles no collision damage. Any thoughts would be appreciated. I have many good electrical tools , power probe-3 and a good fluke 88. I just need direction?

Bob Geco