Impreza Sedan AWD F4-1820cc 1.8L SOHC (1993)
Oxygen Sensor: Testing and Inspection
A faulty oxygen sensor will set code 32 in the on-board diagnostic system. Refer to the schematic diagram and test the sensor with the diagnostic chart.
Wire color code identification:
L:
Blue
B:
Black
Y:
Yellow
G:
Green
R:
Red
W: White
Br: Brown
Lg: Light green
Gr: Gray
Diagnostic Chart
OXYGEN SENSOR DIAGNOSTIC CHART
CHECK ECU VOLTAGE
With engine warmed up and idling, measure voltage between ECU connector terminal (E30)10 and ground. It should read 0.1-1.0V.
NOTE: Problems with the oxygen sensor heater circuit will cause the sensor to deactivate.
CHECK OXYGEN SENSOR
Voltage Test
1.
With engine idling at operating temperature, disconnect oxygen sensor connector.
2.
Measure voltage between oxygen sensor terminal #4 and ground. It should read 0.1-1.0V.
CHECK HARNESS BETWEEN ECU AND OXYGEN SENSOR