The most likely culprit is a bad Input5 wire between the Combo Switch and the BCM. See BCS-8 here, notice that the RH turn, high beam, and taillamps are all on In5 of the matrix:
https://www.nicoclub.com/service-manual ... %2FBCS.pdf
The wiring diagram starts on BCS-58, the Combo Switch connector M27 and BCM connector M65 are on BCS-61. You'll need to inspect the pins for that wire and ohm it end-to-end. If it's a break and not a pin problem, you can cut the wire loose at both ends and run a new parallel wire. Note that the wire color changes between the switch and BCM, but the WD shows no intervening connectors. That means there's a splice buried someplace in the harness which may have gone bad.