P0248 code definition
This DTC refers to Turbocharger Wastegate Solenoid B Range/Performance.
What the P0248 code means
In a turbocharged vehicle, the wastegate diverts exhaust by opening and closing to a certain degree and at certain times. This helps regulate maximum boost pressure, and offers a safeguard to protect the engine as well as the turbocharger itself.
P0248 indicates that the wastegate solenoid circuit has sent a signal to the PCM (powertrain control module) which is outside of the expected voltage, according to the manufacturer’s specifications. This signal tells the PCM that the solenoid is not controlling wastegate activity in the intended manner.
What causes the P0248 code?
Possible causes of this fault include:
- A faulty wastegate solenoid
- Faulty solenoid wiring or connections
- An open or short in the wastegate solenoid B harness
- A wastegate door that is stuck too far open or closed
- A faulty PCM (rare)
What are the symptoms of the P0248 code?
Aside from a stored code and lit malfunction indicator lamp (MIL), there may be rattling or whining in the turbocharger or its pipes, abnormal exhaust smoke, hissing from the wastegate or hoses, poor engine performance, and/or spark plug fouling. In addition, the engine or transmission may get too hot. Other DTCs may present, such as engine misfire, knock sensor, or other turbocharger codes. If the vehicle is equipped with a boost pressure gauge, it will show excessively high boost pressure levels.
How does a mechanic diagnose the P0248 code?
The following may be required to find the source of this fault:
- Hooking a code reader up to check for other faults and to record freeze frame data
- Clearing any DTCs, then road testing the vehicle to see if they return
- Diagnosing and repairing any codes which occurred along with P0248, in the order in which they occurred
- Visually inspecting the wastegate solenoid B and its wiring and connectors
- Checking solenoid voltage and resistance against the manufacturer’s specifications
- Inspecting the wastegate door to see if it’s stuck
- Observing the wastegate door and actuator rod while activating the vacuum pump
Common mistakes when diagnosing the P0248 code
The actuator rod and other involved components are easy to overlook when diagnosing this code. Simply replacing the wastegate solenoid without also making sure that the circuitry is sound and that the wastegate door isn’t stuck may result in repeated solenoid circuit failure.
Another mistake is failing to repair any concurrent boost pressure sensor fault codes. These should be rectified before moving on to fix the wastegate solenoid circuit.
How serious is the P0248 code?
This malfunction most likely will not cause serious damage to other vehicle components, but it could cause problems which affect how well the vehicle runs. If the wastegate solenoid problem is accompanied by a stuck wastegate door, a constant boost condition may result, compromising drivability.
What repairs can fix the P0248 code?
A wastegate solenoid B malfunction may be solved by:
- Repairing solenoid circuitry such as wiring and connectors
- Replacing wastegate solenoid B
- Replacing the PCM (rarely)
Additional comments for consideration regarding the P0248 code
Due to the customized nature of a turbocharged system, there is no predefined layout by which the wastegate solenoids are arranged. “B” simply refers to one of the solenoids in a group which work in sequence – there is no set position where this particular solenoid resides. This means that it’s important to have the relevant documents, including a wiring diagram, for your particular system.
If you’re attempting this repair yourself, don’t forget to retest the system with a scanner once you’ve completed the job. In some cases, a malfunction has multiple causes and fixing just one will result in the DTC returning, in which case you would have to start the diagnostic and repair process all over again.
Need help with a P0248 code?
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