P012D
Turbocharger/Supercharger Inlet Pressure Sensor A Circuit High
Turbo/boost sensing
Generic OBD-II
High
What it means
P012D means the ECM sees an abnormally high voltage from the turbocharger or supercharger inlet pressure sensor A — usually a signal wire shorted to voltage, an open circuit, or a failed sensor. Because this reading helps manage boost, the engine may drop into reduced-power or limp mode. It's an electrical fault first, so check the sensor and its wiring before suspecting the turbo itself.
High
Can I keep driving? Usually driveable but down on power — a bad boost-inlet pressure signal can put the engine in reduced-power or limp mode until it's repaired.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced power or limp (fail-safe) mode
- Sluggish acceleration or lack of boost
- Possible rough running under load
Common causes
Most likely first
- Faulty turbocharger/supercharger inlet pressure sensor ALikely
- Signal wire shorted to voltage or open in the sensor circuitCommon
- Corroded or disconnected connector at the sensorCommon
- Poor ground or reference-voltage fault to the sensorLess often
- Faulty ECM/PCM (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and compare the sensor's live reading against a known-good reference or barometric pressure at key-on.
- Inspect the sensor connector and wiring for a short to voltage, an open, or corrosion.
- Verify the sensor's 5-volt reference and ground are present and clean.
- Test the sensor's resistance/output per the manufacturer's spec; replace it if out of range.
- If wiring and sensor check good, retest the circuit before considering the ECM. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P012D?+
You can usually drive it, but the engine may be in reduced-power mode and slow to respond. Get it diagnosed before heavy or highway use.
Can I just clear P012D?+
It will return if the sensor or its wiring is faulty. Because the ECM uses this signal to manage boost, fix the circuit rather than just clearing.
Related codes
Often seen with P012D
Read & clear P012D yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX