OBD-II code P0248 indicates that the powertrain control module (PCM) has detected a range or performance problem with the turbocharger/supercharger wastegate actuator 'B' control circuit. This typically means the actuator is not moving the wastegate valve as commanded, leading to improper boost pressure control.
The actuator itself may be mechanically stuck, have an internal electrical failure, or a ruptured diaphragm, preventing proper wastegate control.
Damaged, corroded, or loose wiring and connectors between the PCM and the wastegate actuator can cause intermittent or incorrect signals.
Leaks in the vacuum or pressure lines that supply the actuator can prevent it from moving the wastegate valve correctly, leading to range/performance errors.
Carbon buildup or mechanical damage can cause the wastegate valve itself to stick, so the actuator cannot move it through its full range.
A faulty powertrain control module is a very unlikely cause, but if all other components and circuits check out, the PCM may be misinterpreting signals or failing to control the actuator properly.
It means the engine computer has detected a range or performance issue with the wastegate actuator 'B' circuit, which controls turbocharger boost pressure. The actuator is not responding as expected.
Driving with this code is possible but not recommended for long. You may experience reduced power and poor acceleration, and continued driving could cause engine damage from overboost or underboost conditions.
No, PCM failure is very rare for this code. The problem is almost always a faulty wastegate actuator, wiring issue, or vacuum/boost leak. Replacing the PCM without proper diagnosis is a common misdiagnosis and a waste of money.
Start by inspecting the wastegate actuator and its connections. Repair or replace any damaged wiring, vacuum lines, or the actuator itself. If the wastegate valve is stuck, it may need cleaning or replacement. Only after ruling out all other causes should the PCM be considered.