Temp. fix, spray Brake clean on latch(on door)close door several times and then spray wd-40, pb blaster,etc. Most of the time this will take care of the ajar light---FOR AWHILE. IT WILL HAPPEN AGAIN!!!!Pull door panel and unbolt latch and replace with a new door ajar switch, the plunger pin in the old one will be partialy pushed in , compared to new one.The temp fix helps narrow which door is cutting the door ajar light on----switches are cheap, around $10 bucks at dealer.Worked at Ford dealer for 32 years- started using this type of dome light- ajar switch in Rangers around 93, made a lot of peaple happy by spraying latch BUT ajar light came back on most times in cold weather. LOL Blue