Open or shorted fuel injector supply sense circuit wiring, including chafed or corroded wires; Faulty fuel injector group B supply sense circuit connection at the injector harness or PCM; Defective fuel injector(s) within group B causing abnormal current draw; Failed PCM driver or internal circuit for the supply sense; Blown fuse or relay supplying power to the injector group B circuit; Corrosion or water intrusion in the injector harness connectors

DTC codes / P2Cxx · Hybrid propulsion / P2C26

P2C26Fuel Injector Group B Supply Sense Circuit

Q: What does code P2C26 mean?

Fuel Injector Group B Supply Sense Circuit. P2C26 indicates that the powertrain control module (PCM) has detected an abnormal voltage condition on the supply sense circuit for fuel injector group B, which is a set of injectors that share a common power feed. The PCM monitors this circuit to ensure the injectors receive the correct voltage for proper fuel delivery, and when the sensed voltage falls outside the expected range, it sets this code and may disable the affected injectors to protect the engine.

P2C26 indicates that the powertrain control module (PCM) has detected an abnormal voltage condition on the supply sense circuit for fuel injector group B, which is a set of injectors that share a common power feed. The PCM monitors this circuit to ensure the injectors receive the correct voltage for proper fuel delivery, and when the sensed voltage falls outside the expected range, it sets this code and may disable the affected injectors to protect the engine.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaHybrid propulsion

Symptoms you may notice

Illuminated check engine light, often with no other symptoms
Rough idle or misfire, especially noticeable when the engine is cold
Reduced engine power or hesitation during acceleration
Poor fuel economy due to incomplete combustion
Engine may stall or run poorly under load
In some cases, the engine may enter limp mode to protect the catalytic converter

Common causes, most likely first

Open or shorted fuel injector supply sense circuit wiring, including chafed or corroded wires
Faulty fuel injector group B supply sense circuit connection at the injector harness or PCM
Defective fuel injector(s) within group B causing abnormal current draw
Failed PCM driver or internal circuit for the supply sense
Blown fuse or relay supplying power to the injector group B circuit
Corrosion or water intrusion in the injector harness connectors

How to diagnose and fix it

Use a scan tool to verify the code and check for any related injector or misfire codes
Inspect the injector group B supply sense circuit wiring for damage, corrosion, or loose connections
Check the fuse and relay that supply power to the injector group B circuit and replace if faulty
Measure resistance and voltage on the supply sense circuit to compare with manufacturer specifications
Test each fuel injector in group B for proper resistance and compare to the others
If the circuit and injectors test good, suspect the PCM and perform a pinpoint test before replacement
After repairs, clear the code and verify the fix with a test drive and live data monitoring

Don't overlook the supply sense circuit

This code often sets due to a poor connection at the injector harness rather than a failed injector, so a thorough visual inspection of the connectors is critical before replacing parts.
The supply sense circuit is a low-current monitoring wire, and a short to ground or voltage can be intermittent, making the code appear only under certain conditions like vibration or temperature changes.
A faulty fuel injector in group B can cause the PCM to set this code even if the injector still operates, because the current draw may be out of specification.
Some vehicles use a shared power feed for multiple injectors, so a problem with one injector's wiring can affect the entire group and trigger this code.
Misdiagnosis often occurs when technicians replace the PCM without first checking the injector supply sense circuit for continuity and shorts, leading to repeat failures.

Can I keep driving with P2C26?

Driving with this code is not recommended because the engine may run poorly or stall, and continued driving can damage the catalytic converter due to unburned fuel. If you must drive, avoid heavy acceleration and have the vehicle inspected as soon as possible.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.