OBD-II code · Powertrain (generic, extended)
P28BB Cylinder 11 Ion Current Sense Circuit High
Ion current from cylinder 11 is above the expected window. Cross-coupled signal, biased reference, or sensor fault.
Is it safe to drive with P28BB?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyInductive cross-coupling from ignition coil primary
- PossibleSense reference voltage biased
- Less likelyConnector pins corroded - high contact resistance
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–3 h
- Emissions test
- Likely to fail
- Parts involved
- Spark Plug Cyl 11, Ignition Coil Cyl 11, Ion Sense Module
Related codes
- P2893Cylinder 1 Ion Current Sense Circuit High
- P2897Cylinder 2 Ion Current Sense Circuit High
- P289BCylinder 3 Ion Current Sense Circuit High
- P289FCylinder 4 Ion Current Sense Circuit High
- P28A3Cylinder 5 Ion Current Sense Circuit High
- P28A7Cylinder 6 Ion Current Sense Circuit High
- P28ABCylinder 7 Ion Current Sense Circuit High
- P28AFCylinder 8 Ion Current Sense Circuit High
- P28B3Cylinder 9 Ion Current Sense Circuit High
- P28B7Cylinder 10 Ion Current Sense Circuit High
- P28BFCylinder 12 Ion Current Sense Circuit High
- P28B8Cylinder 11 Ion Current Sense Circuit
- P28B9Cylinder 11 Ion Current Sense Circuit Range/Performance
- P28BACylinder 11 Ion Current Sense Circuit Low
- P28BCCylinder 12 Ion Current Sense Circuit
- P28BDCylinder 12 Ion Current Sense Circuit Range/Performance
- P28BECylinder 12 Ion Current Sense Circuit Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.