P0246

P0246 reports the wastegate solenoid A control circuit voltage is above the expected threshold, indicating an open circuit, a short to power, or a disconnected solenoid. Start with the simplest check: confirm the solenoid is plugged in and the connector is not backed out, which is shockingly common after recent service near the engine bay. Measure solenoid resistance (should be 14-30 ohms on most platforms); an infinite reading confirms an open winding. Probe the control circuit at the solenoid harness side with the connector unplugged and the key on: you should see roughly 12V on the supply pin, and the PCM driver pin should sit near 12V at rest and pulse to ground when commanded. The expensive misdiagnosis is replacing a perfectly good turbocharger when a $4 connector pin or a $90 solenoid was the only fault.

Vehicle-specific patterns: 2007-2010 BMW 335i N54 wastegate solenoid connector terminals back out as the rubber seal hardens, producing intermittent P0246 fixed by re-tensioning or replacing the connector; 2011-2014 Ford Edge/Explorer 3.5L EcoBoost wastegate solenoid pigtail fails at the splice inside the harness loom (TSB 14-0036); 2010-2013 Mazdaspeed3 2.3L DISI BCS connector clip breaks and the plug walks off under vibration; 2014-2019 Subaru WRX FA20DIT wastegate solenoid harness pulls tight against the alternator bracket. Estimated repair: $90 to $420.