Circuit Description
The powertrain control module (PCM) monitors the high side refrigerant pressure through a A/C refrigerant pressure sensor. When the pressure is high the signal voltage is high. When the pressure is low the signal voltage is low. When pressure is high the PCM commands the cooling fans on. When pressure is too high or too low the PCM will not allow the A/C compressor clutch to engage.
Conditions for Running the DTC
| • | The A/C refrigerant pressure sensor pressure is more than 453 psi (4.92 volts) with the A/C requested. |
| • | The A/C refrigerant pressure sensor pressure is more than 336 psi (3.76 volts) with the A/C not requested. |
| • | The A/C refrigerant pressure sensor pressure is less than 8.75 psi (0.20 volt) when the intake air temperature is more than 0°C (32°F) and DTCs P0112 or P0113 are not set. |
| • | The A/C refrigerant pressure sensor pressure is less than 0 psi (0.01 volt) when an intake air temperature (IAT) sensor DTC is present or the intake air temperature is less than 0°C (32°F). |
Conditions for Setting the DTC
Any of the conditions for running the DTC are met for 15 seconds.
Action Taken When the DTC Sets
| • | The PCM will not illuminate the Malfunction Indicator Lamp (MIL). |
| • | The PCM stores the failure records. |
| • | The A/C compressor clutch is disabled. |
Conditions for Clearing the DTC
| • | The DTC will become history if the PCM no longer detects a failure. |
| • | The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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Tests for the proper operation of the circuit in the low voltage range.
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Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
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Tests for a short to voltage in the 5-volt reference circuit.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views | ||||
1 | Did you perform the HVAC Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Important: The ambient air temperature must be above 3°C (38°F).
Does the A/C compressor operate? | -- | Go to Step 3 | |
3 |
Important: This step must be performed in an area with an ambient temperature that is more than 0°C (32°F).
Does the scan tool indicate that the A/C High Side Pressure parameter is within the specified range? | 0.2-3.76 V | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 4 |
Does the scan tool indicate that the A/C High Side Pressure parameter is less than the specified value? | 0.2 V | Go to Step 5 | Go to Step 11 | |
Does the scan tool indicate that the A/C High Side Pressure parameter is more than the specified value? | 3.76 V | Go to Step 6 | Go to Step 9 | |
Does the voltage measure less than the specified value? | 5.1 V | Go to Step 7 | Go to Step 8 | |
7 |
Does the resistance measure less than the specified value. | 5 ohms | Go to Step 13 | Go to Step 12 |
8 | Test the 5-volt reference circuit of the A/C refrigerant pressure sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 14 |
9 | Test the 5-volt reference circuit of the A/C refrigerant pressure sensor for a short to ground, a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 10 |
10 | Test the signal circuit of the A/C refrigerant pressure sensor for a short to ground a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 14 |
11 | Test the signal circuit of the A/C refrigerant pressure sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 14 |
12 |
Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 14 |
13 | Inspect for poor connections at the harness connector of the A/C refrigerant pressure sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 15 |
14 | Inspect for poor connections at the harness connector of the powertrain control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 16 |
15 | Replace the A/C refrigerant pressure sensor. Refer to Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement in Heating, Ventilation and Air Conditioning. Did you complete the replacement? | -- | Go to Step 17 | -- |
16 |
Important: Perform the programming procedure for the powertrain control module. Replace the powertrain control module. Refer to Powertrain Control Module Replacement in Engine Controls-2.2L (L61). Did you complete the replacement? | -- | Go to Step 17 | -- |
17 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
