P0249 OBD-II Trouble Code: Turbocharger Wastegate Solenoid B Low

P0249 code definition

The P0249 code indicates that the PCM is detecting an abnormal reading coming from the turbocharger wastegate solenoid “B” circuit.

What the P0249 code means

Circuit B is a specific wastegate solenoid wherein multiple solenoids are used in succession. Your vehicle uses the wastegate solenoid to control and monitor engine boost pressure. The turbocharger wastegate’s opening is regulated by the solenoid valve.

The voltage level being reported may be less than or greater than the ideal range. Whatever the case, the code occurs because the PCM recognizes that the abnormal voltage is a sign of being unable to effectively control wastegate performance.

What causes the P0249 code?

There are a handful of reasons your vehicle may display the P0249 code, but they all have to do with the wastegate solenoid. Common examples are:

• The wastegate solenoid itself could be faulty and thus the voltages being reported are also erroneous.
• Open or shorted wiring inside the Watergate solenoid circuit would cause a similar error.
• Electrical connectors located inside the wastegate solenoid may also be corroded, loose or completely disconnected.

What are the symptoms of the P0249 code?

If the P0249 code is triggered, you’ll most likely notice a reduction in your engine’s ability to accelerate. When you do go to accelerate, your turbo pipes or turbocharger may make rattling noises or even “whine” or otherwise give out a high-pitched sound.

Other common symptoms include things like spark plug fouling, abnormal smoke coming from the exhaust, hissing noises from the hoses and/or turbocharger wastegate and excessive transmission or engine temperature.

How does a mechanic diagnose the P0249 code?

Turbocharging relies on force air induction to get better gains in horsepower. Various sensors are used by the PCM to assess safe levels of boost that still provide optimal performance results from the engine. So the first thing a mechanic will need to do is conduct a thorough overview of the entire turbocharger system.

After initial repairs are taken care of, the mechanic will need to reset the system to see if the code returns, usually after a quick test drive.

The wastegate door may also need to be tested which the mechanic will do with a handheld vacuum pump connected to the wastegate controller.

Common mistakes when diagnosing the P0249 code

Fairly often, the problem is just that the wastegate solenoid harness is either shorted or open, which would cause the P0249 code. This is why you should inspect it first before proceeding to take wires out and possibly doing a lot of unnecessary work.

You also need to make sure that the wastegate door and linkage are working correctly. If you fail to carry out this initial inspection, you’ll continue receiving that code time and time again.

How serious is the P0249 code?

The P0249 code doesn’t represent anything life-threatening. However, the whole reason you went to the trouble of installing and turbocharging your engine is so that it could produce greater amounts of horsepower. Therefore, while the code isn’t going to put your life at risk, for most people, getting it addressed is a huge priority so they can get back to better horsepower.

What repairs can fix the P0249 code?

Fortunately, this is a fairly simple problem for an experienced mechanic to fix. They’ll do one of the following:

• Replace or repair any wires that are disconnected or damaged
• Address any problems with the connectors
• Inspect the turbocharger boost sensor for any problems that would cause an erroneous code
• Check to see if resistance and voltage values are consistent with what the manufacturer’s specifications are

Additional comments for consideration regarding the P0249 code

Never stop at just one problem. For example, if there is a frayed wire, replace it, but keep going through the list of potential problems. The code could be the result of a couple or more issues you’ll want the mechanic to address all at the same time.

Need help with a P0249 code?

If you’d like a certified mobile mechanic to visit you at your home or office, assess the problem with your vehicle and take care of necessary repairs, YourMechanic is here to help. You can receive a free quote and book your appointment online or speak with a service advisor by calling 1-800-701-6230.