Operation CHARM: Car repair manuals for everyone.

Component

CAUTION: Use ONLY a high impedance Digital Volt Ohm Meter (DVOM) when testing components on computerized vehicles.
Be sure the voltmeter is set to read VOLTS only (not ohms). Be sure external voltage is not applied to the sensor lead, as damage to the sensor may occur.

INSPECTION OF VOLTAGE
1. Warm up the engine to normal operating temperature and stop it.
2. Disconnect the Heated Oxygen Sensor connector.
3. Connect a voltmeter to the Heated Oxygen Sensor.
4. Start the engine and increase engine speed at 2000 rpm.
5. Check that the voltage changes between 0.2 - 1.O volts when accelerating and decelerating.

INSPECTION OF HEATER
1. Set your DVOM to Ohm setting.
2. Disconnect the Heated Oxygen Sensor connector.
3. Measure the resistance between the heater terminals.

Resistance: 2 - 5 Ohms (at 2O°C (68°F))
Above 2O°C (68°F): 5 - 30 Ohms


3. If not as specified, replace the Heated Oxygen Sensor.