Diagnostic Aids
WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.
- An inaccurate temperature display indicates an abnormal resistance condition within the system.
- For intermittent diagnosis, refer to Testing for Intermittent Conditions and Poor Connections .
The following table will be used to measure the resistance of the sensor and compare it with the actual ambient temperature. The mirror's temperature accuracy should be within 5 degrees of the actual temperature. The actual temperature should not be taken from a radio station, a sign displaying the temperature, etc. A temperature measuring tool such as a thermometer should be used. Some temperature measuring tools may be within 5 degrees of the actual temperature. Make sure to consult the manufacturer for the accuracy of the tool. This comparison can make the mirror seem off by 5-10 degrees of the actual temperature when it is not.
Ambient Air Temperature Sensor Resistance
| °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 |
Mirrors - Temperature Display Inaccurate
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Inside Rearview Mirror Schematics Connector End View Reference: Mirror Connector End Views |
|||
| 1 | Did you review the Automatic Day-Night Mirror Description and Operation? | Go to Step 2 | Go to Automatic Day-Night Mirror Description and Operation |
| 2 |
IMPORTANT:
Verify the J 33431-C
resistance settings with a DMM.
Disconnect one of the J 33431-C leads momentarily between the resistance settings in order to quickly update the temperature display. |
Go to Step 5 | Go to Step 3 |
| 3 | Test the signal circuit of the ambient temperature sensor for a high resistance. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
Go to Step 9 | Go to Step 4 |
| 4 | Test the ground circuit of the ambient temperature sensor for a high resistance. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
Go to Step 9 | Go to Step 6 |
| 5 | Inspect for poor connections at the harness connector of the ambient temperature sensor. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
Go to Step 9 | Go to Step 7 |
| 6 | Inspect for poor connections at the harness connector of the inside rearview mirror. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
Go to Step 9 | Go to Step 8 |
| 7 | Replace the ambient temperature sensor. Refer to Ambient Air Temperature Sensor Replacement . Did you complete the replacement? |
Go to Step 9 | - |
| 8 | Replace the inside rearview mirror. Refer to Rearview Mirror Replacement
. Did you complete the replacement? |
Go to Step 9 | - |
| 9 | Operate the system in order to verify the repair. Did you correct the condition? |
System OK | Go to Step 2 |