1991 Subaru Justy BaseFACTORY OEM SERVICE PROCEDURE

Sensor Operating Range Charts: Notes

NOTE: Unless stated otherwise in test procedure, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance.
AIRFLOW METER VOLTAGE

Application (1) Volts
Justy (2)
Legacy
ECU Pin No. 8 & Ground (3)
Engine Off 0-13
At Idle 13-14
ECU Pin No. 9 & Ground (3)
Engine Off 0-.3
At Idle .8-1.2
ECU Pin No. 10 & Ground (3)
Engine Off Zero
At Idle Zero
Loyale PFI (4) 1.0-2.0
Loyale TBI: White & Black Wire Terminals (3) 0.1-0.5
XT & XT6: White & Black/Red Wire Terminals (3) 1.0-2.0
(1) Voltage should be higher when blowing air through inlet side of airflow meter.
(2) Justy does not have airflow meter.
(3) Connect voltmeter between these 2 terminals of airflow meter connector.
(4) Connect voltmeter between Black/Red wire terminal and sealed wire terminal next to unused terminal.
AIRFLOW SENSOR RESISTANCE (LEGACY) (1)

Terminal Specification
Red Wire & Ground One Megohm (Min.)
White Wire & Ground One Megohm (Min.)
Black Wire & Ground One Megohm (Min.)
Black/Red Wire & Ground Zero Ohm
(1) Measure resistance between indicated terminal of airflow sensor connector and ground.
AIR TEMP SENSOR RESISTANCE (JUSTY CARB.)(1)

Temperature Ohms
68°F (20°C) 2000-3000
176°F (80°C) 270-370
(1) Measure resistance between air temperature sensor connector terminals.
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