Beyond checking for general defects, what should mass transit bus drivers specifically verify during the after-trip inspection?

AAMVA CDL Manual, Section 4.4 (After-trip Vehicle Inspection), p. 4-3

Mass transit buses have extra passenger-interaction hardware, stop-request signals and door interlocks, that intercity buses don't rely on as heavily. These systems fail silently, so the manual calls them out for a deliberate end-of-shift check.