Subaru Legacy BN/BS (2015-2019) Service Manual: Inspection

Subaru Legacy BN/BS (2015-2019) Service Manual / Fuel injection (fuel systems)(h4do) / Mass air flow and intake air temperature sensor / Inspection

1. CHECK THE MASS AIR FLOW SENSOR UNIT

1. Connect the battery positive terminal to terminal No. 3 and the battery ground terminal to terminal No. 4, and connect the circuit tester positive terminal to terminal No. 5 and the circuit tester ground terminal to terminal No. 4.

2. Check the voltage changes when air is blown to the mass air flow sensor unit in arrow direction.

2. CHECK THE INTAKE AIR TEMPERATURE SENSOR UNIT

Measure the resistance between intake air temperature sensor terminals.

Temperature	Terminal No.	Standard
−20°C (−4°F)	1 and 2	16.0±2.4 k-
20°C (68°F)		2.45±0.24 k-
60°C (140°F)		0.58±0.087 k-

3. OTHER INSPECTIONS

1. Check that the mass air flow and intake air temperature sensor has no deformation, cracks or other damages.

2. Check that the mass air flow and intake air temperature sensor has no dirt.

Removal

1. Disconnect the ground terminal from battery sensor. NOTE2. Disconnect the connector (A) from the mass air flow and intake air temperature sensor, and remove the mass air flow and intake air temper ...

Installation

1. Install the mass air flow and intake air temperature sensor, and connect the connector to the mass air flow and intake air temperature sensor.Tightening torque:1 N·m (0.1 kgf-m, 0.7 ft-lb)2. ...

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