P21E7Cylinder 6 Injector B Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P21E7 is stored when the B injector of cylinder 6 shows a short toward power. GM's 2019 Corvette ZR1 with the LT5 V8 is the documented user; there the FICM checks the low side only in the driver-off state, flags 0.5 Ohm or less to power, and needs at least 11 V at the powertrain relay with the engine running. The result is a Type A fault after one trip. With the low side tied to supply, every switching attempt would push current straight into the driver, so the injector on the right-bank cylinder 6 delivers nothing. A useful check is to unplug the injector: if the voltage on the control wire stays, the harness is at fault; if it disappears, the injector coil is suspect. P21E6 is the matching low fault and P0277 the A injector high code.
- What you may notice
- Check engine light on
- Lean condition on bank 2 under load
- Cylinder 6 misfire at high load
- Likely causes
- LikelyCylinder 6 B injector control wire in contact with a live wire
- PossibleShorted turns in the injector coil
- RareOutput stage of the injection control module damaged by the short
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.