P21E5Cylinder 5 Injector B Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P21E5 means the cylinder 5 B injector circuit is pulled toward supply voltage. GM documents it for the LT5 V8 of the 2019 Corvette ZR1: the FICM looks at the low side of that injector while its driver is off and treats 0.5 Ohm or less toward power as a short. The test needs a running engine and at least 11 V at the powertrain relay, runs continuously and sets a Type A fault. A low side held at supply potential can never be switched to ground, so the injector stays closed. On this engine the port injectors were added mainly to supply extra fuel under boost, so a dead unit tends to show at high load, where cylinder 5 may run lean. The low-side counterpart is P21E4; the A injector of the same cylinder reports P0274 for the same fault type.
- What you may notice
- Check engine light on
- Cylinder 5 lean or hesitant at full load
- Part-load driving often feels normal
- Likely causes
- LikelyLow-side wire of the cylinder 5 B injector shorted to a supply wire
- PossibleSupply and control wire of the injector bridged in the harness
- PossibleInjector coil shorted across its terminals
- RareDamaged output stage in the injection control module
- 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.