DTC P0534
Diagnostic Instructions
DTC Descriptor
DTC P0534: Air Conditioning (A/C) Refrigerant Charge Low
Circuit/System Description
The AC compressor function is to provide refrigerant flow in the AC refrigerant loop to help cool down and dehumidify the for the cabin and help maintain the battery temperature. Rather than a more typical pulley, the A/C compressor uses a 3-phase alternating current, high voltage electric motor to operate. It has an on-board inverter that takes High Voltage direct current from the vehicle's High Voltage Battery and inverts it to alternating current for the motor. The AC compressor shall be activated when any of the three following events occur:
| • | The customer selects ECO or Comfort. |
| • | The HVAC system is fan only but the customer selects defrost mode |
| • | The High Voltage Battery Thermal System requests the AC compressor on to help maintain the battery temperature |
The Hybrid Powertrain control module 2 (HPCM2) uses values from the A/C refrigerant pressure transducers, A/C refrigerant thermistor, ambient air temperature sensor, cabin climate control request, battery cell temperature sensors, battery coolant temperature sensors and battery coolant pumps to determine the speed at which the compressor will operate. This message is sent from the HPCM2 to the A/C compressor control module via serial data message.
Conditions for Running the DTC
DTC P0534 Case 1
| • | 12V battery system voltage is equal to or greater than 10.25V |
| • | The air conditioning compressor control module has 300V |
| • | The A/C compressor motor is running for at least 30 seconds. |
| • | Must be in battery active cooling mode for at least 1 minute |
| • | The following DTCs must not be set: P0CE0; P0CE2; P0CE3; P0CE6; P0CE7; P1CE7; P1CE8, P0C47; P0C4A, P1F18, P0C44, P0C45, P0C43,P0CD6, p0CD7, P0CD8, P0071; P0072; P0073 |
DTC P0534 Case 2
| • | 12V battery system voltage is equal to or greater than 10.25V |
| • | AC compressor off for greater than 240 seconds |
| • | Outside air temperature greater than 15C. (59F) |
| • | The following DTCs must not be set: P2516, P2517, P2518, P0606, P0071,P0072, P0073 |
DTC P0534 Case 3
| • | 12V battery system voltage is equal to or greater than 10.25V |
| • | AC compressor on for greater than 240 seconds |
| • | Outside air temperature greater than 5C (41F). |
| • | The following DTCs must not be set: P2516, P2517, P2518, P0606, P0071,P0072, P0073 |
DTC P0534 Case 4
| • | 12V battery system voltage is equal to or greater than 10.25V |
| • | A/C compressor off for greater than 240 seconds |
| • | The following DTCs must not be set: P0531,P0532, P0533,P0606, P0071; P0072; P0073 |
Conditions for Setting the DTC
DTC P0534 Case 1
The difference between the hybrid/EV battery pack coolant outlet temperature and hybrid/EV battery pack coolant inlet temperature within the evaluation period of 120 seconds is less than a calibrated amount of 3 to 5 degrees. The required temperature difference requirement is based on outside air temperature and whether the cabin blower is on or off.
DTC P0534 Case 2
Low side pressure is a less than a designated value based on outside air temperature.
DTC P0534 Case 3
Low side pressure is less than 150 kPa (21.75 PSI) for outside air temperature greater than 5C (41F).
DTC P0534 Case 4
High side pressure is greater than 5000 kPa (725 PSI)
Action Taken When the DTC Sets
The A/C compressor control module is disabled.
Conditions for Clearing the DTC
P0534 is a type B DTC.
Reference Information
Schematic Reference
HVAC Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Automatic HVAC Description and Operation
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Diagnostic Aids
P1EC3 is the hybrid/EV battery pack heater circuit fault DTC. It diagnoses three different circuit faults (short-ground, short-battery, open circuit); one of these, short to ground, could cause the hybrid/EV battery pack heater to activate and could cause P0534 to set. Diagnose P1EC3 before diagnosing P0534.
Circuit/System Verification
- Verify that DTC P1EC3 is not set.
- Verify that DTC P0534 is not set.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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