P013
Code PO13:
Oxygen Sensor Circuit:
DESCRIPTION:
The PCM provides a 0.45 volt reference to the oxygen sensor on CKT 412. When the oxygen sensor reaches operating temperature it will generate a counter voltage that will vary based on the amount of oxygen in the exhaust. The rear oxygen sensor is located in the manifold before the catalytic convertor. A lean exhaust will generate a low voltage and cause the 0.45 reference to move lower. A rich exhaust will generate a high voltage and cause the 0.45 reference to move higher. If the oxygen sensor can't respond under the test conditions and generate a voltage greater or less than the 0.45 reference, it will set a Code P013. Possible causes of Code P013 are:
1. Open in CKT 412 or 413.
2. Short to voltage on CKT 412 or 413.
3. Oxygen sensor that cannot respond.
TEST CONDITIONS:
1. Codes P014, P015, P021, P022, P026, and P027 not set.
2. Coolant temperature 81.5°C or greater.
3. Throttle angle between 5 and 29.8 degrees.
4. Throttle position switch open.
5. RPM 800 or greater.
FAILURE CONDITIONS:
Oxygen sensor voltage stays between 0.307 volt and 0.609 volt for more than 64 seconds (oxygen sensor voltage not toggling), Code P013 is set.
ACTION TAKEN:
1. PCM turns 'ON' the 'SERVICE ENGINE SOON' MIL
2. PCM enables evaporative emission control solenoid if Code P017 is also set.
3. 'Closed Loop' operation disabled.
NOTES ON FAULT TREE:
1. Voltage on PCM data parameter PD33 should fluctuate above 0.6 volt and below 0.3 volt. If voltage remains above 0.6 volt, check CKT 412 for a short to voltage. If voltage remains below 0.3 volt check CKT 412 for a short to ground.
2. Measuring voltage with a voltmeter will isolate a sensor/wiring problem from a PCM problem. If voltage fluctuates above 0.6 volt and below 0.3 volts, the fault is with the PCM. If voltage remains below 0.3 volt, check CKT 412 for a short to ground or CKT 413 for a short to voltage. If voltage remains above 0.6 volt, check CKT 412 for a short to voltage. If voltage remains between 0.3 volt and 0.6 volt, check CKT 412 and CKT 413 for an open.