DTC Confirmation Test (Overall Function Test)
NOTE:
Use the following test to check overall function of HO2S circuit. During this test, 1st trip DTC may not be confirmed.
NOTE:
If DTC confirmation test has been previously performed, always turn ignition off and wait at least 10 seconds before performing next DTC confirmation test.
NOTE:
Before proceeding, ensure ambient temperature is more than 14°F (-10°C) and battery voltage is more than 11 volts at idle.
CAUTION:
DO NOT use ECM ground terminals when measuring voltage.
- Start engine and warm to normal operating temperature. Measure voltage between ground and ECM terminal No. 94 (bank 1) or No. 62 (bank 2) by backprobing. See Figure.
- While observing voltmeter, increase engine speed to 2000 RPM. The following conditions should exist:
- Maximum voltage should be less than 0.8 volt at least once.
- Minimum voltage should be less than 0.35 volt at least once.
If voltage is not as specified, go to DIAGNOSTIC PROCEDURE . If voltage is as specified, system is okay at this time.