Hummer H2. Manual — part 247

Ambient Air Temperature Sensor Resistance

Mirrors - Temperature Displays SC or OC

°C

°F

Minimum Resistance

K Ohms

Maximum Resistance

K Ohms

-35

-31

234.81

250.59

-30

-22

171.69

182.31

-25

-13

126.82

133.99

-20

-4

94.63

99.49

-15

5

71.30

74.58

-10

14

54.21

56.43

-5

23

41.48

43.17

0

32

32.00

33.31

5

41

24.96

25.83

10

50

19.61

20.19

15

59

15.49

15.94

20

68

12.31

12.67

25

77

9.85

10.12

30

86

7.96

8.15

35

95

6.45

6.61

40

104

5.27

5.39

45

113

4.32

4.42

50

122

3.56

3.64

55

131

2.95

3.02

60

140

2.46

2.52

Step

Action

Yes

No

Schematic Reference:Inside Rearview Mirror Schematics
Connector End View Reference:Stationary Windows Connector End Views

1

Did you review the temperature display operation of
the inside rearview mirror and perform the necessary
inspections?

Go to Step 2

Go to

Symptoms -

Stationary

Windows

2

1. Turn ON the ignition, with the engine OFF.

2. Turn ON the temperature display on the inside

rearview mirror.

Does the temperature display show a temperature
reading?

Go to Step 3

Go to Step 5

3

Does the temperature display show an accurate
temperature reading?

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

Go to Step 4

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Stationary Windows - Hummer H2

4

1. Turn OFF the ignition.

2. Disconnect the ambient air temperature sensor.

3. Measure the resistance of the ambient air

temperature from the sensor signal circuit to the
low reference circuit of the sensor.

4. Compare the ambient air temperature sensor

resistance reading with the chart above.

Is the ambient air temperature sensor resistance within
the range specified in the chart above?

Go to Step 12

Go to Step 13

5

Does the temperature display show SC?

Go to Step 6

Go to Step 7

6

1. Turn OFF the ignition.

2. Disconnect the ambient air temperature sensor.

3. Turn ON the ignition, with the engine OFF.

Does the temperature display show SC?

Go to Step 9

Go to Step 13

7

1. Turn OFF the ignition.

2. Disconnect the ambient air temperature sensor.

3. Connect a 3-amp fused jumper between the

signal circuit of the ambient air temperature
sensor and a good ground.

4. Turn ON the ignition, with the engine OFF.

Does the temperature display show SC?

Go to Step 8

Go to Step 10

8

1. Turn OFF the ignition.

2. Connect a 3-amp fused jumper between the

signal circuit and the low reference circuit of
the ambient air temperature sensor.

3. Turn ON the ignition, with the engine OFF.

Does the mirror temperature display show SC?

Go to Step 13

Go to Step 11

9

Test the signal circuit of the ambient air temperature
sensor for a short to ground. Refer to Circuit Testing
and to Wiring Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 17

Go to Step 14

10

Test the signal circuit of the ambient air temperature
sensor for an open or for a short to battery positive
voltage. Refer to Circuit Testing and to Wiring
Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 17

Go to Step 14

Test the low reference circuit of the ambient air
temperature sensor for an open or for a high

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Stationary Windows - Hummer H2

MIRRORS - COMPASS DISPLAY INOPERATIVE OR INACCURATE

Mirrors - Compass Display Inoperative or Inaccurate

11

resistance. Refer to Circuit Testing and to Wiring
Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 17

Go to Step 14

12

Test the signal and low reference circuits of the
ambient air temperature sensor for high resistance.
Refer to Circuit Testing and to Wiring Repairs in
Wiring Systems.
Did you find and correct the condition?

Go to Step 17

Go to Step 14

13

Inspect for a poor connection at the harness connector
of the ambient air temperature sensor. Refer to
Testing for Intermittent Conditions and Poor
Connections and to Connector Repairs in Wiring
Systems.
Did you find and correct the condition?

Go to Step 17

Go to Step 15

14

Inspect for a poor connection at the harness connector
of the inside rearview mirror. Refer to Testing for
Intermittent Conditions and Poor Connections and
to Connector Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 17

Go to Step 16

15

Replace the ambient air temperature sensor. Refer to
Ambient Air Temperature Sensor Replacement .
Did you complete the replacement?

Go to Step 17

-

16

Replace the inside rearview mirror. Refer to
Rearview Mirror Replacement .Did you complete
the replacement?

IMPORTANT:

For the inside rearview mirror with a compass,
perform Compass Calibration and Variance
Procedure .

Go to Step 17

-

17

Operate the system in order to verify the repair.
Did you correct the condition?

System OK

Go to Step 3

Step

Action

Yes

No

Schematic Reference:Inside Rearview Mirror Schematics
Connector End View Reference:Stationary Windows Connector End Views

1

Did you review the compass operation of the inside
rearview mirror and perform the necessary inspections?

Go to

Step 2

Go to Symptoms -

Stationary Windows

2

Does the automatic day-night feature of the inside rearview
mirror operate correctly?

Go to

Step 3

Go to Mirrors - Automatic

Day-Night Inoperative

1. Turn ON the ignition, with the engine OFF.

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Stationary Windows - Hummer H2

REPAIR INSTRUCTIONS

AMBIENT AIR TEMPERATURE SENSOR REPLACEMENT

Removal Procedure

3

2. Turn ON the compass.

3. Verify that the compass has one of the following

conditions:

z

An incorrect reading on the display.

z

The letter "C" or "CAL" is displayed.

z

The compass display is blank.

Does the compass have one of the conditions mentioned
above?

Go to

Step 4

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

4

Is the compass display totally blank?

Go to

Step 8

Go to Step 5

5

Is the letter "C" or "CAL" displayed on the mirror?

Go to

Step 6

Go to Step 7

6

Perform the compass calibration procedure. Refer to
Compass Calibration and Variance Procedure .
Is the compass accurate and operating properly?

Go to

Step 10

Go to Step 7

7

Perform the compass magnetic variation adjustment
procedure. Refer to Compass Calibration and Variance
Procedure .
Is the compass accurate and operating properly?

Go to

Step 10

Go to Step 8

8

Inspect for a poor connection at the harness connector of the
inside rearview mirror. Refer to Testing for Intermittent
Conditions and Poor Connections and to Connector
Repairs in Wiring Systems.
Did you find and correct the condition?

Go to

Step 10

Go to Step 9

9

Replace the inside rearview mirror. Refer to Rearview
Mirror Replacement .Did you complete the replacement?

IMPORTANT:

Perform Compass Calibration and Variance Procedure
for the inside rearview mirror with compass.

Go to

Step 10

-

10

Operate the system in order to verify the repair.
Did you correct the condition?

System

OK

Go to Step 3

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Stationary Windows - Hummer H2