P012DTurbocharger/Supercharger Inlet Pressure Sensor A Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- The turbocharger/supercharger inlet pressure sensor A sits ahead of the compressor – between air filter and turbocharger, or on GM's supercharged V8 between throttle and supercharger. It is an analogue 5 V pressure sensor used for the compressor pressure ratio, filter restriction and cross-checks with the other pressure sensors. P012D means the signal voltage is above its upper limit – typically the signal wire shorted to the 5 V reference or battery voltage, or an open sensor ground that lets the signal rise to the reference. GM's supercharged LT4/LT5 sets it above 97 % of the reference (about 124 kPa) with 320 of 400 samples failing, monitored continuously; two trips on the LT4, one on the 2019 LT5. FCA documented false settings on the 2019 Jeep Wrangler 2.0 turbo, fixed by new engine software. The control module substitutes a modelled or ambient value and may limit boost.
- What you may notice
- Check engine light on
- Reduced power or limp mode possible
- Often no noticeable symptoms
- Likely causes
- LikelySignal wire shorted to 5 V reference or battery voltage
- PossibleSensor ground open or connector corroded
- PossibleSensor faulty internally
- RareControl module software (false setting)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.