Legacy Wagon 4WD F4-2.2L SOHC (1991)
Air Flow Sensor Testing
CHECK ECU VOLTAGE
1.
With ignition "ON," measure voltage across ECU connector terminals and ground as follows:
Connector & terminal:
Voltage:
(B48)8-Ground
10-13V (engine "OFF")
13-14V (engine at idle)
(B48)9-Ground
0-0.3V (engine "OFF")
0.8--1.2V (engine at idle)
(B48)10-Ground
0V (engine "OFF")
0V (engine at idle)
CHECK ECU HARNESS AND RESISTANCE
1.
Disconnect ECU and air flow sensor connectors.
2.
Measure resistance between ECU and air flow sensor connectors as follows:
Connector & terminal:
Resistance:
(B48)8-(B1)1
0 Ohm
(B48)9-(B1)4
0 Ohm
(B48)10-(B1)2
0 Ohm
3.
Measure resistance between air flow sensor connector and ground:
Connector & terminal:
Resistance:
(B1)1-Ground
1M Ohms min.
(B1)4-Ground
1M Ohms min.
(B1)2-Ground
1M Ohms min.
(B1)3-Ground
0 Ohm
