Powertrain
Definition only
Lights the check engine lamp
P2AAA: Engine Coolant Bypass Valve B Position Sensor Circuit High
Standardized SAE J2012 code · P2Axx codes
What does P2AAA mean?
Voltage on the engine coolant bypass valve B position sensor signal line is above the expected window. Wire shorted to B+ or sensor open.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Common causes
- High Signal wire shorted to B+
- Medium Open sensor
- Low Connector pins corroded - high contact resistance
Likelihood is a general estimate across vehicles; your make and model may differ.
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P2AAA in the community
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