Exit light never worked.

I have a 2012 144 low top with the exit light option. The driver/shotgun door lights have worked fine. The cargo slider door lamp has never come on.
I have checked the bulb and it is fine. There is no power to the bulb connector. I know the door "open" sensor works because the alert on the dash comes on if the door is ajar.

( Sportsmobile did put a switch for a overhead light in the B pillar. )

I have not yet taken off the B pillar cover. I suppose I should have taken the van back to the dealer initially but I always assumed I just needed to replace a bulb. I'm also not sure it's worth wasting a day at the dealer for something so minor.

Any suggestions on where to look next for a solution?

Thanks.

do you also have the light above the rear doors? Mine has a three position switch-lights controlled by door switch//off//lights on. This switch effects all lights in the cargo area.

Unplug the light fixture and check the connections a volt meter. My bulb is finicky. Yet to burn one out yet, seems it has to be in there "just right". Ive had to re install it about 4 times in the last 50k miles. I've never figured out why it does this. Only the side door acts up.