What Does It Mean?
This is a generic powertrain diagnostic trouble code (DTC) that applies to many OBD-II vehicles (1996-newer). This may include, but is not limited to, vehicles from General Motors, Honda, Dodge, Ford, BMW, Mercedes, etc. Although generic, the exact repair steps may vary depending on the year, make, model, and powertrain configuration.
OBD-II fault codes P06A0, P06A1, and P06A2 are associated with the variable A/C compressor control circuit.
The purpose of the variable A/C compressor control circuit is to engage and disengage the compressor at the appropriate time to maintain the desired temperature inside the vehicle’s cabin. The ECU receives voltage signals from various components to detect potential malfunctions within the system.
The variable A/C compressor control circuit includes several components to accomplish this process. Most newer automobiles are equipped with air conditioning, which is an essential element for this circuit to function correctly.
When the engine control unit (ECU) detects abnormally high electrical signals in the variable A/C compressor control circuit, code P06A2 is set, and the check engine light is activated.
A Typical A/C Compressor:
P06A2 A/C Compressor
How Severe Is This DTC?
The severity of this code is moderate to severe depending on the specific nature of the problem. While it is a convenient feature for the user, air conditioning malfunctions can progress, leading to significant repair requirements when not corrected in a timely manner.
What Are Some of the Symptoms of the Code?
Symptoms of a P06A2 fault code may include:
The air conditioner will not work properly
Check engine light on
What Are Some Common Causes of the Code?
Causes
of this P06A2 code may include:
Faulty A/C compressor
Faulty A/C solenoid (if applicable)
Undercharged or overcharged system
Clogged orifice tube or dryer
Faulty climate control
Faulty A/C relay
Blown fuse or fusible link (if applicable)
Corroded or damaged connector
Faulty or damaged wiring
Faulty ECU
What Are the P06A2 Troubleshooting Steps?
The first step in the troubleshooting process for any malfunction is to search for technical service bulletins (TSBs) for the specific vehicle by year, model, and powertrain. In some circumstances, this can save a lot of time in the long run by pointing you in the right direction.
The second step is to locate all components of this circuit and perform a thorough visual inspection to check that the associated wiring does not have obvious defects such as scraping, rubbing, exposed wires, or burn marks. Then, check the connectors for security, corrosion, and damaged pins. This process should include the A/C compressor, associated sensors, relays, and the ECU.
Advanced Steps
Advanced steps become very vehicle-specific and require appropriate advanced equipment to function accurately. These procedures require a digital multimeter and vehicle-specific technical references. The ideal tool for this troubleshooting process is an A/C diagnostic machine, if available.
This specialized equipment is essential for locating the source of the malfunction by identifying leaks and verifying proper pressures in the system. High and low side gauges will also validate the integrity of the A/C compressor and associated components. Restrictions within the system, such as a clogged orifice tube or dryer, will also be identified. The proper amount of refrigerant in the system also plays a key role in the operation of this circuit. Safety switches, fuses, and fusible links are often incorporated to prevent damage to the A/C compressor.
Voltage Checks
Specific troubleshooting guidelines must be referenced to determine the required voltage ranges for various A/C components. Depending on the configuration, several components are integrated, including the A/C compressor, relays, and solenoids for certain applications. The climate control in newer automobiles can make the troubleshooting process extremely complicated in some cases. Voltage requirements vary depending on the specific year and model of the vehicle.
If this process identifies the absence of a power source or ground, continuity tests may be required to verify the integrity of the wiring, connectors, and other components. Continuity tests should always be performed with the power disconnected from the circuit, and normal readings for wiring and connections should be 0 ohms of resistance. Resistance or lack of continuity is an indication of faulty wiring that is open or short-circuited and must be repaired or replaced.
What Are the Common Repairs for This Code?
Replacement of the A/C compressor
Replacement of the A/C solenoid (if applicable)
Replacement of the orifice tube or dryer
Replacement of the blown fuse or fusible link (if applicable)
Repairing the A/C system leak
Cleaning corrosion from connectors
Repairing or replacing faulty wiring
Evacuating and recharging the system
Flashing or replacing the ECU
Misdiagnosis can lead to replacing the A/C compressor or other associated components when wiring, connectors, or incorrect charge are the cause of the problem.
I hope the information in this article has been helpful in pointing you in the right direction to correct the issue with your variable A/C compressor control circuit fault code. This article is strictly informational, and the technical data and service bulletins specific to your vehicle should always take priority.