Circuit Description
The right A/C temperature sensor is a thermistor that controls signal voltage to the heater and A/C programmer. The heater and A/C programmer supplies voltage on CKT 517. When the sensor is cold, the resistance is high and the heater and A/C programmer senses a high signal voltage at terminal B7, connector C2. When the sensor warms, the resistance is reduced and the signal voltage is pulled low through CKT 61. Signal voltage will vary from 5 V (open circuit) to 0 V (short circuit).
Conditions for Setting the DTC
| • | The ignition is on. |
| • | The circuit is open or shorted. |
Action Taken When the DTC Sets
| • | A default value of 128 counts and 24 degrees C (75 degrees F) will be used by the heater and A/C programmer. |
| • | The default valve allows the system to operate. |
| • | If air delivery is on A/C or bi-level, the air mix two door will cycle between full cold and full hot. |
Conditions for Clearing the DTC
| • | Use a Scan Tool . |
| • | A history DTC will clear after 50 consecutive ignition cycles have occurred without a malfunction. |
| • | Battery voltage to the body control module is interrupted. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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Perform the Body Control Module (BCM) Diagnostic System Check before continuing with the diagnosis of this DTC.
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This step ensures that the DTC was not set in error.
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This step determines whether the cause of the malfunction is the sensor or an open/short in a circuit.
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The Scan Tool tests for proper sensor operation. Clear all of the DTCs after the repair procedures are complete.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Did you perform the BCM Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - Body Control System in Body Control System | |
2 |
Is the specified voltage measured? | 4.5-5.5 V | Go to Step 3 | Go to Step 6 |
Did the DTC reset? | -- | Go to Step 4 | ||
Did the right A/C temperature sensor voltage decrease? | -- | Go to Step 5 | Go to Step 6 | |
5 | Replace the sensor. Refer to Air Conditioning (A/C) Temperature Sensor Replacement . Is the repair complete? | -- | Go to Step 9 | -- |
6 | Inspect CKT 61 (YEL) for an open or short. Was an open or short condition located? | -- | Go to Step 8 | Go to Step 7 |
7 |
Is the replacement complete? | -- | Go to Step 9 | -- |
8 | Repair an open or short in CKT 61 (YEL). Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Step 9 | -- |
Use the Scan Tool in order to clear all of the DTCs. Confirm proper operation of the A/C system. Is the A/C system operating normally? | -- | -- |
