P053BPCV Heater A Control Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- The PCV heater is an electric element of a few ohms (Saab: 6–10 Ω) at the junction of the ventilation hose and the intake; it stops water in the blow-by gas from freezing and blocking the ventilation in frost. The module switches it to ground. P053B means the low-side control line is shorted to ground, so the heater stays on regardless of command – it works in frost, but heats permanently. GM's diesels of 2016 check it with 20 of 40 samples below 90 °C coolant without warning lamp, GM Europe's 2.0 CDTI in the Saab 9-5 with the lamp on the first trip – a difference even within GM.
- What you may notice
- Check engine light (depending on the maker)
- Heater permanently on
- Usually no change in driving
- Likely causes
- LikelyControl line chafed against ground
- PossibleHeating element shorted to its housing
- RareEngine module driver shorted
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €0 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.