Code 13: O2 Sensor-Open/Shorted CKT (SOHC): Notes
The ECM supplies a .45 volt signal between terminals D6 and D7. When oxygen sensor reaches operating temperature, it varies this voltage from approximately .1-.9 volt (lean to rich exhaust). Oxygen sensor does not produce voltage when temperature is less than 600°F (360°C) or when engine operates in open loop.
NOTE:
Test numbers refer to test numbers on diagnostic chart.
- Code 13 will set if all the following conditions are met for 40 seconds:
- Engine temperature is greater than 157°F (69°C).
- Engine has been running for at least 5 minutes after start.
- O2 signal voltage steady between .35 and .55 volt.
- Throttle angle greater than 5 percent.
If conditions for Code 13 exist, system will not go into closed loop.
- This determines if sensor, wiring or ECM is the cause of Code 13.
- Use only a high impedance (10-megohm) digital volt/ohmmeter. This tests continuity of circuits No. 412 and 413. If circuit No. 413 is open, ECM voltage on circuit No. 412 will be greater than .6 volt.