Diagnostic Trouble Code (Dtc) P0449 Evaporative Emission (Evap) Control System Vent Valve/Solenoid Circuit Malfunction - Isuzu 1999 RODEO Workshop Manual

DIAGNOSTIC TROUBLE CODE (DTC) P0449 EVAPORATIVE EMISSION (EVAP)
CONTROL SYSTEM VENT VALVE/SOLENOID CIRCUIT MALFUNCTION
Circuit Description
The Powertrain Control Module (PCM) controls the
Evaporative Emission (EVAP) Canister Vent Solenoid
Valve through the use of a control (ground) circuit. If the
PCM commands the Vent solenoid but the voltage
remains High (12 Volts); or, if the PCM commands the
Vent solenoid OFF but the voltage remains Low (0 volts),
then DTC P0449 will set. DTC P0449 is a type A code.
Conditions for Setting the DTC
f Ignition voltage is greater than 10 volts.
f Engine run time is greater than 32 seconds.
The above mentioned conditions are met and one of the
following two conditions are met for 25 seconds within a
50 seconds test sample:
f PCM senses voltage is High with the EVAP Canister
Vent Solenoid commanded ON.
f PCM senses voltage is Low with the EVAP Canister
Vent Solenoid commanded OFF.
Action Taken When the DTC Sets
f The PCM will illuminate the Malfunction Indicator Lamp
(MIL).
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
f The PCM will store the conditions that were present
when the DTC was set as Freeze Frame and in Failure
Records.
Conditions for Clearing the MIL/DTC
f The PCM will turn OFF the MIL after three consecutive
trips without a reported failure.
f A History DTC will clear after 40 consecutive trips
without a reported failure.
f The DTC can be cleared using the Scan Tool's "Clear
Info" function.
Diagnostic Aids
f Poor connections , or a damaged harness – Inspect the
harness connectors for: backed–out terminals,
improper mating or damaged terminals. Also check for
open circuits, shorts to ground, and shorts to voltage.
f The Fuel Pressure Sensor shares a 5 Volt reference
with the MAP sensor and TP sensor.
If these codes are also set, it could indicate a
problem with the 5 Volt reference circuit or
components itself.
f The Fuel Pressure Sensor share a ground with the
MAP sensor and the TP sensor.
6E1–267
D06RX056