HOLDEN GEN III V8, Service Training

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GEN III V8 ENGINE MANAGEMENT
Four Wire Heated Oxygen Sensor Circuit
A failure in the Heated Oxygen Sensors or circuits will set one of the following DTCs:
DTC P0131 Heated Oxygen Sensor Circuit Low Voltage Bank 1 Sensor 1
Conditions for running DTC P0131
Criteria 1
• DTCs P 0 1 0 1 , P0102, P0103, P0112, P0113,
P 0 1 1 7 , P 0 1 1 8 , P 0 1 2 1 , P0122, P0123, P0335,
P0336, P0351, P0358, P1258 are not set
• The engine coolant temperature is greater than
48°C
• The ignition voltage is greater than 9 0 volts
• The fuel system is operating in Closed Loop
• The fuel trim learn is enabled
• The air/fuel ratio is between 1 4 5 and 1 4 7 1
• The TP angle is between 0% and 70%
Conditions for setting DTC P0131
Criteria 1
• The H02S signal voltage remains below 200
mV
• The Criteria 1 conditions are present for at least
33 seconds
Criteria 2
• DTCs P0101, P0102, P0103, P 0 1 1 2 , P 0 1 1 3 ,
P 0 1 1 7 , P 0 1 1 8 , P0121, P0122, P0123, P0335,
P0336, P0351, P0358, P1258 are not set
• The ignition voltage is greater than 9 0 volts
• The Power Enrichment mode is enabled for at
least 0 5 seconds
Criteria 2
• The H02S signal voltage remains below 360
mV
• The Criteria 2 conditions are present for at least
five seconds
Action taken when DTC P0131 Sets
• The PCM illuminates the Check Powertrain Lamp when the diagnostic runs and fails
• The PCM records the operating conditions at the time the diagnostic fails The PCM stores this information
in the Freeze Frame/Failure Records
• Open Loop Fueling
Conditions for clearing the Check Powertrain Lamp and DTC P0131
• The PCM turns the Check Powertrain Lamp OFF after one ignition cycle that the diagnostic runs and does
not fails
• A last test failed (current DTC) clears when the diagnostic runs and does not fail
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