OBD-II code · Powertrain (generic, extended)
P2AAB Engine Coolant Bypass Valve B Position Sensor Circuit Intermittent/Erratic
The engine coolant bypass valve B position sensor signal drops out or jumps intermittently. Loose connector or noisy ground.
Is it safe to drive with P2AAB?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySensor connector not seated
- PossibleNoisy ground reference
- Less likelyConnector with intermittent contact under vibration
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–3 h
- Emissions test
- Usually unaffected
- Parts involved
- Engine Coolant Bypass Valve B Position Sensor, Wiring Harness, Ecm
Related codes
- P26A8Engine Coolant Bypass Valve A Position Sensor Circuit Intermittent/Erratic
- P2AA8Engine Coolant Bypass Valve B Position Sensor Range/Performance
- P2AA9Engine Coolant Bypass Valve B Position Sensor Circuit Low
- P2AAAEngine Coolant Bypass Valve B Position Sensor Circuit High
- P2AACDiesel Fuel Presence Sensor Circuit
- P2AADDiesel Fuel Presence Sensor Range/Performance
- P2AAEDiesel Fuel Presence Sensor Circuit Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.