GM Service Manual Online
For 1990-2009 cars only

Sensor Resistance Table Volts to Temp to Resistance

Voltage Tech 2 (V)

R Nominal (k ohms)

Outside Air Temp (°F)

Outside Air Temp (°C)

4.72-4.74

171.6

-22

-30

4.52-4.54

94.63

-4

-20

4.22-4.25

54.21

14

-10

3.81-3.85

32.00

32

0

3.31-3.34

19.61

50

10

2.76-2.79

12.31

68

20

2.22-2.25

7.959

86

30

1.73-1.75

5.268

104

40

1.31-1.34

3.563

122

50

0.99-1.01

2.458

140

60

The Tech 2 will display sensor value as a voltage. This gives the approximate voltage expected at different ambient temperatures as well as what should be read with an ohmmeter connected to the sensor. Since this is raw data any heat from underhood that changes ambient temp around the sensor might skew the reading, so let the engine compartment cool.