Powertrain, generic (extended)

P2C26 Fuel Injector Group B Supply Sense Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Many engines feed their injectors in groups from a switched supply, for example through an injector relay or a high-side driver. A separate sense line lets the engine module read back whether voltage really arrives at group B. P2C26 is the general fault of that read-back: the sensed value is missing, erratic or not consistent with the commanded supply state. It differs from P2149–P2151, which concern the supply path of group B itself. No publicly accessible manufacturer document explains P2C26; the code rests on CARB's comprehensive component rules. GM's injector logic on the Saab 9-5 2.0T shows the general pattern for supply faults: an incorrect voltage for over 1 s with the engine above 80 rpm sets a Type B code and the injector is shut off. Misfire is possible.

Likely causes

Open or high-resistance sense wire between injector supply and module
Injector relay or its socket making poor contact
Corroded connector in the injector supply harness
Faulty sense input inside the engine control module

Symptoms

  • Check engine light
  • Possible misfire or rough running on the cylinders of group B
  • Hard starting if the group is switched off

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–600
Time0.5–3 h

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

Parts involved

fuel injector group bwiring harnessecm

Related codes

P2C27P2C28P2149P2150P2151P0685

References: law.cornell.edu, saabwisonline.com.