Diagnostic Trouble Code (Dtc) 1404 Exhaust Gas Recirculation (Egr) Closed Valve - Isuzu 1999 RODEO Workshop Manual

DIAGNOSTIC TROUBLE CODE (DTC) 1404 EXHAUST GAS RECIRCULATION
Circuit Description
The powertrain control module (PCM) monitors the
exhaust gas recirculation(EGR) valve pintle position input
to ensure that the valve responds properly to commands
from the PCM to detect a fault if the pintle position sensor
and control circuits are open or shorted. If the PCM
detects a pintle position signal voltage below the normal
range of the pintle position sensor, or a signal voltage that
is not within a tolerance considered acceptable for proper
EGR control system operation, the PCM will set a DTC
P1404.
Conditions for Setting the DTC
f IAT is above 5°C (41°)
f EGR actual position is 16 counts below the EGR low
threshold for at least 6.3 seconds.
Action Taken When the DTC Sets
f The PCM will illuminate the Malfunction Indicator Lamp
(MIL) after the second consecutive trip in which the
fault is detected.
f The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
f The PCM will turn the MIL OFF on the third consecutive
trip cycle during which the diagnostic has been run and
the fault condition is no longer present.
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
(EGR) CLOSED VALVE
f A history DTC P1404 will clear after 40 consecutive
warm up cylcles without a fault.
f DTC P1404 can be cleared by using the Scan Tool's
"Clear Info" function.
Diagnostic Aids
Check for the following conditions:
f Excessive deposits on EGR valve pintle or seat –
Check for deposits that may interfere with the EGR
valve pintle extending completely or cause the pintle to
stick.
f Poor connection or damaged harness – Inspect the
wiring harness for damage. If the harness appears to
be OK, observe the EGR actual position display on the
Tech 2 while moving connectors and wiring harnesses
related to the EGR valve. A change in the display will
indicate the location of the fault.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
NOTE: If the EGR valve show signs of excessive heat,
check the exhaust system for blockage (possible a
plugged catalytic converter) using the "Restricted
Exhaust System Check".
6E1–337
D06RX055