that's NOT the PIR1 for an 18F46K22 according to my datasheet copy...
maybe others can confirm but I'm guessing that's part of your problem.
I didn't ...
I'm going to learn LIN protocol for that i use uc PIC18f46k22 and LIN driver ic
MCP2021 and CCS PCH v5.008. I find LIN Bus sample example of PIC16F687/89/90 in CCS PCH v5.008 but ...