DTC 13

Fig. 028 Chart - Code 13 Open Oxygen Sensor Circuit:

Fig. 029 - Wiring Diagram for Code 13 Open Oxygen Sensor Circuit. VIN P:

CODE 13

OXYGEN SENSOR CIRCUIT

2.0L "J" SERIES

FUEL INJECTION (TBI)

Code 13 WILL SET:
a. Engine at normal operating temperature
b. At least 2 minutes engine time after start.
c. O2 signal voltage at terminal D7 of ECM steady between .35 and .55 volts for more than one minute.
d. Throttle position sensor signal above 6 % (about .3 volts above closed throttle voltage).
e. All conditions must be met for about 60 seconds.
The ECM supplies a voltage of about .45 volt between terminals "D7" and "D6". (If measured with a 10 megohm digital voltmeter, this may read as low as .32 volts.) The O2 sensor varies the voltage within a range of about 1 volt if the exhaust is rich, down through about .10 volt if exhaust is lean.
The sensor is like an open circuit and produces no voltage when it is below 360°C (600°F). An open sensor circuit or cold sensor causes open loop operation.
1. Grounding the diagnostic terminal with the engine running enables the "Field Service Mode", which allows the ECM to confirm either open or closed loop operation using the "CHECK ENGINE" light.
2. This step verifies no additional code stored, and that stored Code 13 is intermittent. See DIAGNOSIS BY SYMPTOM.
3. This step simulates a lean exhaust. If the ECM and wiring are OK the ECM will see the lean condition and turn the "CHECK ENGINE" light off for at least 30 seconds after engine start, and then flash "open loop". It should be considered normal if the light remains off for a longer period of time before flashing open loop.