Diagnostic Trouble Code (Dtc) P1133 - Isuzu 1999 RODEO Workshop Manual

6E1–320 RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
DIAGNOSTIC TROUBLE CODE (DTC) P1133 O2 SENSOR INSUFFICIENT
Circuit Description
The powertrain control module (PCM) monitors the
heated oxygen sensor (HO2S) activity for 90 seconds
after "Closed Loop" has been enabled. During this test
period the PCM counts the number of times that the
HO2S signal voltage crosses the rich–to–lean and
lean–to–rich threshold. If the PCM determines that the
HO2S did not switch enough times, Diagnostic Trouble
Code P1133 will be set.
A lean–to–rich switch is determined when the HO2S
voltage changes above and below 450 mV. DTC P1133 is
a type B code.
Conditions for Setting the DTC
f Engine coolant temperature (ECT) is above 60°C
(140°F).
f Engine is operating in "Closed Loop".
f The engine has been running at least two minutes.
f Canister purge duty cycle is greater than 2%.
f Calculated air flow between 17 and 32 grams/sec.
f Engine speed is between 1500 RPM and 3500 RPM.
f Above conditions are present for 1 second.
f 90 seconds after "Closed Loop" and has been
achieved, the PCM monitors the oxygen sensor as it
switches above and below 450 mV. If fewer than 12
rich–to–lean and 12 lean–to–rich switches are
detected, Diagnostic Trouble Code P1133 will be set.
SWITCHING (BANK 1 SENSOR 1)
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 "Open Loop" fuel control will be in effect.
f The PCM will store conditions which were present
when the Diagnostic Trouble Code 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.
f A history Diagnostic Trouble Code P1133 will clear
after 40 consecutive warm–up cycles have occurred
without a fault.
f Diagnostic Trouble Code P1133 can be cleared by
using the Scan Tool's "Clear Info" function.
Diagnostic Aids
A malfunction in the HO2S heater ignition feed or ground
circuit may cause a Diagnostic Trouble Code P1133 to
set. Check HO2S heater circuitry for intermittent faults or
poor connections. If connections and wiring are OK and
Diagnostic Trouble Code P1133 continues to set, replace
the Bank 1 HO2S 1.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help to determine how often
D06RX046