Powertrain, generic · Fuel and air metering (injector circuit)

P02C7 Cylinder 12 - Fuel Trim at Min Limit

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

These codes belong to an individual-cylinder fuel correction: a diesel's cylinder balance control measures each cylinder's crankshaft acceleration and adjusts its injection quantity; on petrol engines a cylinder-selective mixture control does the same. CARB requires the system to report when such a correction has used up its range or one cylinder causes an imbalance. P02C7 means the correction for cylinder 12 is at its lower limit: the module keeps taking fuel away from this cylinder and still cannot even it out – a sign that it receives too much fuel, for example from a dripping injector. Cylinder 12 only exists on engines with twelve or more cylinders. GM and Ford use other codes for this (P0263 ff, P219A ff); no manufacturer document describing this code with thresholds was found, so the description follows CARB and published patents.

Likely causes

Injector of cylinder 12 dripping or leaking
Injector with excessive flow (worn seat or needle)
Wrong injector correction code after replacement
Injector circuit short (extended activation)

Symptoms

  • Check engine light on
  • Rough idle, vibration
  • Higher consumption, smoke or fuel smell

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€150–900
Time1–4 h

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

Parts involved

fuel injector cylinder 12crankshaft position sensorengine control module

Related codes

P02C6P02C8P02C9P0172P0296P232D

References: law.cornell.edu, patents.google.com, patents.google.com.