P0246 Code Fix: Wastegate Boost Solenoid A High (Wiring First)

What Does P0246 Mean?

A modern turbo engine controls boost with a small electric solenoid. The boost-control or wastegate solenoid A gets a switched 12V feed on one wire, and the PCM grounds the other wire with a varying duty cycle to bleed pressure and set how far the wastegate opens. That controls how much boost the turbo makes. The PCM watches the solenoid circuit electrically the whole time. P0246 is the code for boost-control solenoid A when the PCM sees the control circuit go high or shorted to voltage instead of switching cleanly between ground and rest.

"High" describes the electrical state of the circuit, not the amount of boost. When the PCM drives the solenoid and the control line reads high or stuck at voltage, it cannot trust the circuit, so it usually pulls boost back and protects the turbo. The short list of reasons: a control wire shorted to 12V, a connector shorting the control pin to the feed pin, a solenoid coil shorted internally, or a failed driver inside the PCM. P0246 has a sister code: P0245 is the same solenoid A circuit reading Low or Open. P0243 and P0244 are the related Wastegate Solenoid A Open and Range/Performance codes.

Here is the part that saves money. A circuit has three pieces: the solenoid, the wiring, and the connector that joins them. The phrase "turbocharger boost control" pushes people toward the turbo, but the turbo is mechanical and P0246 is electrical. The control wire and connector fail far more often than the turbo does, especially in the hot, vibrating zone around the turbo where insulation chafes through and shorts to a powered surface. A shorted wire produces the same P0246 a bad solenoid would. The job is to find which of the three pieces failed, and that test costs nothing.

What Are the Symptoms of P0246?

Symptoms depend on whether the PCM has dropped into limp mode and how the wastegate is sitting with the solenoid faulted. A hard short cuts boost control and the drop in power is obvious. An intermittent short comes and goes:

Is P0246 Serious?

Moderate to high. Unregulated boost can overboost and damage the turbo, so handle it within about a week.

The mechanical urgency is real. When boost control is lost, the turbo can overboost and a sustained overboost can damage the turbocharger or cause knock, both of which cost far more than the P0246 repair behind them. The financial risk runs the other way: the frequent error is paying for a turbo or a solenoid that was never the problem. Handle the code quickly, but spend the free ten minutes confirming whether the fault is wiring, connector, or solenoid before buying parts.

What Causes a P0246 Code?

The list below runs from most common to rarest. The wiring and connector sit at the top, the solenoid is in the middle, and the turbo itself is not on the electrical list at all.

What You'll Need

How Do You Fix a P0246 Code?

Work the steps in order. Step 2, the coil-resistance test, and Step 4, the short-to-power check, separate a bad solenoid from bad wiring in minutes and are the ones most people skip.

• 1

  Scan All Codes and Note the Companions

  Record every code. P0246 often travels with P0245 (Solenoid A Circuit Low, the sister code), P0243 and P0244 (Wastegate Solenoid A Open and Range/Performance), P0234 (Overboost), P0299 (Underboost), and P0046 (Boost Control Circuit Range/Performance). P0246 alone points to an electrical high or short on the boost-control solenoid A circuit. P0246 with a boost or limp-mode code means the solenoid is not regulating the wastegate. P0246 next to several unrelated codes points to a shared feed or ground. Clear the codes and restart: if it returns at once, a hard fault exists, so go to Step 2; if it stays gone, clean and re-seat the connector as cheap insurance.

  A reader that shows P0246 next to a pile of unrelated electrical codes usually means a shared power or ground problem. Chase the feed and ground, not the turbo.
• 2

  Boost Solenoid Coil Resistance Test

  This is the test that decides solenoid versus wiring. Unplug the boost control solenoid A connector, set the meter to ohms, and measure across the solenoid's two terminals. Most boost and wastegate solenoids read about 14 to 30 ohms; confirm the figure in the service manual. A reading near zero means a shorted coil, which can drive the circuit high, so replace the solenoid. A reading of OL or infinite means an open coil, which usually sets the Low or Open code P0245 or P0243 instead. A reading inside spec means the solenoid is healthy and the high signal is in the wiring or connector, so leave it alone and go to Step 3. Write the reading down. An in-spec number is what keeps you from buying a solenoid, or a turbo, you do not need.

• 3

  Inspect the Connector and Pins

  A failing connector or an internal short causes P0246 more often than a bad solenoid. Check the boost solenoid connector for green or white corrosion, oil intrusion, melted plastic, pushed-back pins, and a cracked locking tab. Probe each terminal for tension, since loose or splayed pins can touch the feed pin and short the control wire high. Look for two pins bridged by debris or a connector body melted enough to weld the control and feed together. Reconnect and run a wiggle test with live data on screen, moving the connector and harness while you watch the boost-solenoid duty or boost reading. Clean the terminals with contact cleaner, re-tension the pins or fit a new pigtail, add dielectric grease, and seat the connector until it clicks.

  Heat-soak and oil mist near the turbo are the usual reasons a boost solenoid connector degrades. A clean-up and repin here runs $0 to $40 and resolves a large share of cases.
• 4

  Test the Wiring for a Short to Power

  Because P0246 is the High code, the prime suspect is a short to voltage on the control wire. The PCM grounds the solenoid to drive it, so the control circuit should rest near battery voltage and pull low when commanded. With the solenoid unplugged and the key off, check the control wire for a short to 12V or to another circuit at the chafe points where the harness crosses the engine, the turbo heat shield, or the intake. A control wire rubbed through against a hot or powered surface reads high and sets P0246. Back-probe the feed wire with the key on and expect battery voltage within half a volt. Confirm the PCM ground reads under 0.5 ohms. Repair any chafed or shorted wire with solder and heat-shrink, and route it clear of heat with loom.

• 5

  Command the Solenoid and Watch Boost

  Run this cross-check before spending money on the turbo. With a bidirectional scan tool, command the boost-control solenoid on and off and watch the duty cycle and boost-pressure live data respond. If the solenoid clicks and boost tracks the command with the wiring repaired, the circuit is healthy and the repair is done. If the duty reads pinned high or the solenoid does not respond after the wiring checks out, the solenoid is the fault and you replace it, a $30 to $150 part. This actuation test takes the guesswork out and stops people condemning the turbocharger over an electrical fault on the solenoid.

• 6

  PCM Driver or Turbo Mechanicals, Last Resort

  If Steps 2 through 5 clear the solenoid, connector, and wiring, and the circuit still reads high, the PCM's solenoid driver may have failed. This is the rarest outcome. Before authorizing PCM work, document an in-spec coil reading, a clean connector with good pin tension, no short to power on the control wire, and a solenoid that will not respond to actuation. Only then look at wastegate mechanicals, a stuck wastegate or leaking actuator, which a separate code like P0234 or P0299 usually flags. Some specialists repair the PCM driver; otherwise the PCM is reflashed or replaced and programmed to the VIN, $300 to $1,200 with programming.

How Much Does P0246 Cost to Fix?

The cost swings from nothing, for a cleaned connector, to about $1,200 for a PCM driver, with a turbo only in play if a separate mechanical code says so. The free coil-resistance and short-to-power tests decide which end you land on before any parts are bought.

A vehicle with an active P0246 and a Check Engine Light fails OBD-II emissions inspection in most states, and an unregulated turbo can damage itself through overboost. Per the EPA Vehicle Emissions I/M Program, emissions parts are covered under the federal emissions warranty for the first 8 years or 80,000 miles on many vehicles, so verify coverage with your dealer by VIN before paying out of pocket on a newer car.

Which Vehicles Are Most Prone to P0246?

P0246 can show up on any turbo or supercharged engine with an electric boost-control solenoid. Ford EcoBoost V6s, VW and Audi 2.0T engines, BMW turbos, and diesel trucks are where it surfaces most. Platform notes follow the table.

P0246 on Ford 2.7L and 3.5L EcoBoost

On F-150, Explorer, and Edge EcoBoost engines, the boost-control solenoid wiring runs through a hot, tight area near the turbos, so a chafed control wire shorting to power is the usual P0246 cause. The repair is to find the rub-through, solder and heat-shrink it, and re-route the wire clear of the heat shield with loom, $10 to $80. The connector can also corrode from oil mist. A genuinely shorted solenoid happens but is the minority case, so confirm it with the Step 2 resistance test and the Step 5 actuation before buying. The turbo itself is almost never the P0246 fix on these trucks.

P0246 on VW and Audi 1.8T and 2.0T

On VW and Audi 2.0T engines, the boost-control valve and its harness sit in a warm, vibration-heavy spot, so a chafed control wire or a corroded connector reads high and sets P0246. Clean or replace the connector, add dielectric grease, and inspect the harness for a short to power against the head or intake. The boost solenoid itself is an affordable part, $30 to $150, so confirming wiring versus solenoid with the coil test and actuation saves the most here, especially against a dealer turbo quote.

P0246 on BMW N20, N55, B46, and B58 Turbo

BMW turbo engines see P0246 mostly from connector pin-tension loss and harness chafe in the hot zone around the turbo, where the control wire can short to a powered surface even though the connector looks fine, so re-tension or replace the terminals and repair the harness. BMW dealer rates make an unnecessary turbo or solenoid job costly, so the free coil and short-to-power tests pay off the most on these cars.

Should You DIY or Call a Mechanic?

Related Codes You May See With P0246

Frequently Asked Questions