Operation CHARM: Car repair manuals for everyone.

Air Temperature Sensor ( Ambient / Intake ): Testing and Inspection

PROCEDURE
1. Disconnect the wire harness connector from the sensor.

2. Test the resistance of the sensor with a input impedance (digital) volt-ohmmeter.

^ The resistance should be less than 1000 ohms with the engine warm. Replace the sensor if it is not within the range of resistance specified in the chart.

3. Test the resistance of the wire harness.

^ This is done between the engine controller wire harness connector (terminal 2) and the sensor connector terminal. Also check continuity between terminal 4 to the sensor connector terminal. Repair the wire harness as necessary if the resistance is greater than 1 ohm.




TEMPERATURE RESISTANCE (OHMS)

°C °F MIN MAX


-40 -4O 291,490 381,710

-20 -4 85,850 108,390

-10 14 49,250 61,430

0 32 29,330 35,990

10 50 17,990 21,810

20 68 11,370 13,610

25 77 9,120 10,880

30 86 7,370 8,750

40 104 4,900 5,750

50 122 3,330 3,880

60 14O 2,310 2,670

70 158 1,630 1,870

80 176 1,170 1,340

90 194 860 970

100 212 640 720

110 230 480 540

120 248 370 410