P21E3Cylinder 4 Injector B Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P21E3 marks a high circuit state on the cylinder 4 B injector, normally a short to a supply line. On Mitsubishi's 2022 Eclipse Cross, where B is the direct high-pressure injector, the fault must persist 2 s; it closes the manual's list of direct injector circuit codes for the four cylinders. Because the direct injector driver uses boosted voltage, Mitsubishi tells technicians not to probe the terminals with a voltmeter and to work with resistance and continuity checks instead. GM's 2019 LT5 V8 assigns the same code to the supplemental injector of cylinder 4, stored as Type A when the low side sits within 0.5 Ohm of power with the driver off. The low counterpart is P21E2, the port injector high code on Mitsubishi P0271; from P21E4 on, the series continues with cylinder 5.
- What you may notice
- Check engine light on
- Misfire on cylinder 4 (P0304)
- Engine runs with reduced torque if further cylinders are affected
- Likely causes
- LikelyCylinder 4 injector line shorted to a supply wire
- PossibleInjector of cylinder 4 shorted internally
- RareDriver stage in the ECM or injection module damaged
- 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.