What does it mean?
This generic powertrain/engine diagnostic code generally applies to turbocharged and supercharged engines, including but not limited to some Audi, Ford, GM, Mercedes, Mitsubishi, VW, and Volvo vehicles.
The Powertrain Control Module (PCM) controls the boost pressure in a gasoline or diesel engine by managing the output circuit to the wastegate/boost control solenoid valve “A”.
Depending on how the manufacturer activates the solenoid, when the PCM provides power or ground to energize the solenoid and the PCM detects that voltage is already present in a circuit where it shouldn’t be, the PCM will set code P0246. This code is considered an electrical circuit fault only.
Troubleshooting steps may vary depending on the manufacturer, the type of wastegate/boost pressure control, and the color of the control solenoid wires.
Symptoms
Symptoms of a P0246 engine code may include:
Malfunction Indicator Light illuminated
Instrument cluster message alerting the driver to the condition
Lack of power
Causes
Causes
Possible reasons for setting this code include:
Open in the control circuit (ground circuit) between the wastegate/boost control solenoid valve A and the PCM
Open in the power supply circuit between the wastegate/boost control solenoid A and the PCM
Short to power in the control circuit (power-controlled circuit) between the wastegate/boost control solenoid A and the PCM
Wastegate/boost control solenoid valve A
Possibly a failed PCM (highly unlikely)
Diagnostic and Repair Procedures
A good starting point is always to check the Technical Service Bulletins (TSBs) for your specific vehicle. Your issue might be a known problem with a published fix from the manufacturer, which could save you time and money during diagnosis.
Next, locate the “A” wastegate/boost control solenoid on your specific vehicle. Once located, visually inspect the connectors and wiring. Look for scratches, rubbing, exposed wires, burns, or melted plastic. Disconnect the connectors and carefully inspect the terminals (the metal parts) inside the connectors. Check if they appear burnt or have a greenish tint indicating corrosion. Use electrical contact cleaner and a plastic-bristled brush if terminal cleaning is necessary. Allow it to dry and apply electrical grease where the terminals make contact.
The most common failure is due to connection issues.
If you have a scan tool, clear the diagnostic codes from memory and see if P0246 returns. If it does not, the connections were likely your problem.
If the code returns, we will need to test the solenoid and its associated circuits. Typically, there are 2 wires to the wastegate/boost control solenoid. First, disconnect the wiring harness going to the wastegate/boost control solenoid. With a digital volt-ohm meter (DVOM), connect one meter lead to one terminal of the solenoid. Connect the remaining meter lead to the other terminal of the solenoid. It should not be open or shorted. Check the resistance specifications for your specific vehicle. If the solenoid is open or shorted (infinite resistance or no resistance/0 ohms), replace the solenoid.
If this test passes, use a DVOM to ensure there is 12V on the wastegate/boost control solenoid power circuit (red lead to the solenoid power circuit, black lead to a good ground). Make sure the ignition is on. If there is no 12 volts at the solenoid, or if there is 12 volts when the ignition is off, repair the wiring from the PCM or relay to the solenoid, or possibly a faulty PCM.
If that is okay, check that the wastegate/boost control solenoid is properly grounded. Connect a test light to the 12V battery positive (red terminal) and touch the other end of the test light to the ground circuit going to the wastegate/boost control solenoid circuit ground. Using the scan tool to activate the wastegate/boost control solenoid, check if the test light illuminates each time the scan tool activates the solenoid valve. If the test light does not illuminate, it would indicate a circuit problem. If it lights up, wiggle the wiring harness going to the solenoid to see if the test light flickers, indicating an intermittent connection.
If all tests have passed so far and you continue to get a P0246 code, it would most likely indicate a failing wastegate/boost control solenoid, although a faulty PCM cannot be ruled out until the solenoid has been replaced. If in doubt, seek assistance from a qualified automotive diagnostician. PCMs need to be programmed or calibrated to the vehicle to be installed correctly.