Passport 4WD V6-3.2L SOHC (6VD1) (1994)
Oxygen Sensor: Testing and Inspection
Circuit Description
The Generator Charging Circuit supplies Battery voltage to the Heater part of Heated Oxygen Sensor (HO2S). The Heater warms the HO2S to
allow a varying voltage to be produced by the HO2S more rapidly instead of waiting for the HO2S to heat-up on its own.
Test Description
Number(s) below refer to circled number(s) on the diagnostic chart.
NOTE: The following test procedures are for the Heater part of the HO2S. No malfunction Diagnostic Trouble Codes (DTCs) will be logged if
the Heater fails to function properly.
1. This will verify that Battery positive voltage is present for the Heater.
2. This check will test the ground Circuit to the Heater.