Diagnostic Trouble Code (Dtc) P0443 Evaporative Emission (Evap) Control System Purge Control Valve Circuit Malfunction - Isuzu 1999 RODEO Workshop Manual

6E1–260 RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
DIAGNOSTIC TROUBLE CODE (DTC) P0443 EVAPORATIVE EMISSION (EVAP)
CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT MALFUNCTION
Circuit Description
The Powertrain Control Module (PCM) controls the
Evaporative Emission (EVAP) Canister Purge Solenoid
Valve through the use of a control (ground) circuit. If the
PCM commands the Purge solenoid to maximum duty
cycle (100%) but the voltage remains High (12 Volts); or, if
the PCM commands the Purge solenoid to minimum duty
cycle (0%) but the voltage remains Low (0 volts), then
DTC P0443 will set. DTC P0443 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
Purge Solenoid commanded ON.
f PCM senses voltage is Low with the EVAP Canister
Purge Solenoid commanded OFF.
Action Taken When the DTC Sets
f The PCM will illuminate the Malfunction Indicator Lamp
(MIL) the first time the fault is detected.
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.
D06RX056