Powertrain, generic (extended)

P21DF Cylinder 2 Injector B Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P21DF is set when the cylinder 2 B injector circuit shows a short toward supply. Mitsubishi's 2022 Eclipse Cross applies it to the direct high-pressure injector and stores it after a 2 s short with the ignition on and the driver supply above 10 V; troubleshooting first inspects the negative DI wire of cylinder 2 up to the engine module and names the injector, the harness and the ECM as possible causes. The fail-safe is graded: with one cylinder affected, both injectors of that cylinder stop; with several, the engine falls back to port injection and torque is limited. GM's 2019 LT5 V8 judges the same title on its supplemental injector by less than 0.5 Ohm toward power on the low side, Type A. The port injector high code of this Mitsubishi cylinder would be P0265; P21DE is the low fault.

Likely causes

Negative injector line of cylinder 2 shorted to supply
Injector coil shorted
ECM or injection module driver defective

Symptoms

  • Check engine light on
  • Cylinder 2 switched off or misfiring
  • Less pulling power with multiple faults

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–900
Time1–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel injectorinjector wiringengine control module

Related codes

P21DEP21D0P0265P21DCP21E1P0302

References: mitsubishitechinfo.com, gsi.ext.gm.com.