V12 91 Boot lock incorporating boot light switch

Hello Folks,
Got a problem with the boot (trunk) interior lights not working. Have checked the wiring to the connector in the boot lid and disconnected

(foto) in order to check continuity of the light switch circuit which is incorporated in the boot lock mechanism. All i’ve achieved thus far is both boot lights glowing dim like there’s a bad earth problem. Wondered if anyone has had this problem and resolved it.
Any advice appreciated. Thanx in anticipation. Charlie.