Note. For circuit reference, see DTC P0441 schematic.
Circuit Description
Evaporative (EVAP) emission canister purge is controlled by a solenoid valve which allows ported vacuum to purge canister when energized by PCM. A vacuum switch in purge line is used to detect when system is being purged. PCM supplies and reads a 5-volt reference to switch. If switch is open (purge detected) when commanded by PCM, DTC P0442 is set.