Has this been this way since '06?
Have you removed the switch and tested?
How many wires present to the switch?
Single or double pole switch?
The cover pops off the switch, 2 screws holds it in place.
If there are 3 wires and the switch is single pole, then it is possible that the handle light is incorrectly wired directly to to 12v "hot" lead.
If there 3 wires and a double pole switch, then you have a defective pole in the switch.
If you don't have 3 wires, look for a connection under the passenger armrest (lift out the slanted panel in the bottom of the pocket) which could be mis-wired.
If none of the above, you should still have a connection inside the armrest, add a switch.
Do you have keyless entry?? If you do it should be Essex.
Problem could be a hang in the unlock mode which on my '06 the handle an porch light illuminates briefly upon unlock.
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