Powertrain, generic · Vehicle speed, idle control and auxiliary inputs
P053C PCV Heater A Control Circuit High
Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo
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. P053C means the control line is shorted to positive: the driver cannot switch, the heater stays off, or the driver overloads and switches off. 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.
Likely causes
Control line shorted to 12 V
Heating element shorted internally (very low resistance, overcurrent)
Engine module
Symptoms
- Often none, except in frost
- Check engine light (depending on the maker)
- In frost: oil leaks or loss of power from frozen ventilation
Repair estimate
DifficultyEasyDIY possible
Parts and labour€0–250
Time0.3–1.5 h
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
pcv heaterheater wiringengine control module
Related codes
References: gsi.ext.gm.com, saabwisonline.com.