Circuit Description
WARNING: This page is about a different car, the 2002 Isuzu Rodeo Sport, 2002 Isuzu Rodeo, 2002 Isuzu Axiom, and 2002 Honda Passport. However, it is still accessible from the selected car via links, so may be relevant.
Canister vent valve is controlled by PCM. PCM monitors vacuum level via Fuel Vapor Pressure (FVP) sensor input. At an appropriate time, Evaporative (EVAP) canister vent valve is ON, allowing engine vacuum to draw a small vacuum on entire EVAP emission system.
When DTC sets, PCM will not illuminate MIL. PCM will store conditions present when DTC was set as FAILURE RECORDS data only.
PCM will turn MIL off on third consecutive trip cycle during which diagnostic runs and fault is no longer recognized. A history DTC P0448 will clear after 40 consecutive trip cycles during which diagnostic runs and fault is no longer recognized. DTC can be cleared with scan tool, or by disconnecting battery voltage feed to PCM.