Circuit Description
The inside air temperature sensor is a thermistor used to control the signal voltage in the electronic climate control module. The electronic climate control module supplies a reference voltage (about 5 volts) on CKT 734 (DK GRN) to the sensor. When the inside air temperature is cold, the thermistor resistance is high. Therefore, the electronic climate control module will receive a high voltage input. If the outside air temperature is hot, the thermistor resistance is low. Therefore, the electronic climate control module will receive a low signal voltage input. Refer to Sensor Resistance Table .
Conditions for Setting the DTC
When the ignition is switch is in the ON position, the electronic climate control module will detect DTC B0165 any time CKT 734 (DK GRN) is at or near zero voltage.
Action Taken When the DTC Sets
The electronic climate control module will use a default value of 75°F (or 88 A/D counts) until the fault is cleared.
Conditions for Clearing the MIL/DTC
This fault will clear as soon as the fault goes away or has been repaired. The system will then return to normal operation. History DTCs can only be cleared by removing and restoring B+ or by using the scan tool.
Diagnostic Aids
| • | The electronic climate control module may set class 2 lost communication DTCs when the body control module (BCM) or the vehicle control module (VCM) is being reprogrammed. After reprogramming, inspect for DTCs in the electronic climate control module. Clear any history U DTCs, then resume diagnostics. |
| • | Visually inspect the sensor connector and harness for corrosion and damage. The resistance value of the sensor must be witin 300-170,000 ohms. Refer to Diagnostic System Check . If resistance is not within specifications, replace the sensor. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step measures the resistance of the passenger compartment inside air temperature sensor.
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This step inspects for a short to ground in CKT 734 (DK GRN).
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This step inspects for intermittents and tests for a malfunctioning electronic climate control module.
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This step repairs the short to ground in CKT 734 (DK GRN).
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This step replaces a defective inside air temperature sensor.
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This step replaces a defective electronic climate control module.
Step | Action | Value(s) | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
Tools Required
| ||||||||
1 | Was the Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check | ||||
Is the resistance within the range specified in the table? | -- | Go to Step 3 | Go to Step 6 | |||||
Is continuity present? | -- | Go to Step 5 | Go to Step 4 | |||||
Does the DTC reset? | -- | Go to Step 7 | Go to Intermittents and Poor Connections Diagnosis n Wiring Systems | |||||
Repair the short to ground in CKT 734 (DK GRN). Is the repair complete? | -- | Go to Diagnostic System Check | -- | |||||
Replace the inside air temperature sensor. Is the replacement complete? | -- | Go to Diagnostic System Check | -- | |||||
Replace the electronic climate control module. Is the replacement complete? | -- | Go to Diagnostic System Check | -- | |||||
