This could be related to the body control module. That is the module that is responsible for controlling the lights.
We have a short to power at some point. It could be integral to the BCM or there could be a short at a different point. To eliminate the BCM, remove fuse 6 in the interior fuse box. Do the lights turn off with that fuse removed, and the key off?
Let me know. I attached the schematic showing that the fuse powers the left signal at the BCM. Pic 2 shows the fuse location.
Let me know when you turn the key on if the left signal lamps turn off.
Try this and let me know what you find.
See pics below.
Images (Click to enlarge)
Tuesday, December 27th, 2022 AT 9:48 PM