Powertrain, generic (extended)

P22DD Cylinder 2 Alternative Fuel Injector Control Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P22DD signals an interruption in the circuit of the cylinder 2 gas injector. On many systems that circuit is not driven by the engine computer: Ford's 2003 bi-fuel CNG trucks used a separate alternative fuel control module holding drivers for both injector sets, with heavier stages for the gas injectors because they draw more current. GM's 2014 bi-fuel Silverado likewise stores gas faults in its own CNG control module (bulletin PIP5181), so a scan tool has to read that module as well. No maker documents P22DD publicly; TransEco and Ford list only the cylinder 2 Low/High codes P22DE and P22DF, and TransEco assigns an open line to Low. Look for a burnt coil or a separated connector before blaming the module.

Likely causes

Burnt-out or open coil in the cylinder 2 gas injector
Connector at the cylinder 2 injector loose or pulled off
Wire break between gas control module and injector
Failed injector driver in the separate gas control module

Symptoms

  • Malfunction indicator lamp on
  • Gas mode not available or ends shortly after switching
  • Misfire on cylinder 2 when running on gas

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€40–400
Time0.5–2.5 h

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

Parts involved

alternative fuel injector

Related codes

P22DEP22DFP22E0P22D9P0202P0302

References: static.nhtsa.gov, static.nhtsa.gov, http:, law.cornell.edu.