The engine control module (ECM) monitors the high side refrigerant pressure via 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 too high the powertrain control module (PCM) will not allow the A/C compressor clutch to engage.
This diagnostic procedure supports the following DTC:
DTC P0530 Air Conditioning Refrigerant Pressure Sensor Circuit
The ECM detects an A/C request.
• | The A/C refrigerant pressure sensor signal is less than 0.1 volts for 5 seconds. |
• | The A/C refrigerant pressure sensor signal is greater than 4.9 volts for 5 seconds. |
The malfunction indicator lamp (MIL) will not illuminate.
• | The DTC will become history if the ECM no longer detects a failure. |
• | The history DTC will clear after 40 fault-free ignition cycles. |
• | The DTC can be cleared with a scan tool. |
For an intermittent, refer to Testing for Intermittent Conditions and Poor Connections.
The number below refers to the step number on the diagnostic table.
Step | Action | Value(s) | Yes | No | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views | ||||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||||
2 | Does the scan tool indicate that DTC P0530 is current? | -- | Go to Step 3 | Go to Diagnostic Aids | ||||||||
3 |
Does the voltage measure near the specified value? | 5 V | Go to Step 5 | Go to Step 4 | ||||||||
4 | Measure the voltage from the 5-volt reference circuit of the A/C refrigerant pressure sensor to a good ground. Does the voltage measure near the specified value? | 5 V | Go to Step 7 | Go to Step 6 | ||||||||
Does the voltage measure less than the specified value? | 1.5 V | Go to Step 8 | Go to Step 9 | |||||||||
6 | Test the 5-volt reference circuit of the A/C refrigerant pressure sensor for the following:
Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 | ||||||||
7 | Test the low reference circuit of the A/C refrigerant pressure sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 | ||||||||
8 | Test the signal circuit of the A/C refrigerant pressure sensor for the following:
Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 10 | ||||||||
9 | 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. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 11 | ||||||||
10 | Inspect for poor connections at the harness connector of the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 | ||||||||
11 | Replace the A/C refrigerant pressure sensor. Refer to Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement. Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||||
12 | Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||||
13 |
Does the DTC reset? | -- | Go to Step 2 | System OK |