Huh? CAN is a communication protocol, it has nothing to do with how bulb resistance is detected. I mean, maybe the thing that detects it can communicate over CAN to another ECU to tell it about what it has detected, but that has nothing to do with the detection itself. The communication could use any protocol... like K-line (ISO-9141) for example.
CAN is a relatively new protocol... I think the earliest occurrences of it that I've heard of are from the mid-90s. And it's NOT used on the diagnostic OBD port on any Lexuses before 2006. Older Lexuses use ISO-9141 or variants thereof for OBD diagnostics.
Also, it's OBD (On-Board Diagnostics), not ODB (Ol' Dirty Bastard)