P2C27 code meaning
Fuel Injector Group B Supply Sense Circuit Low
Powertrain system Generic code P2Cxx codes Check engine light
What P2C27 means
P2C27 reports that the voltage read back on the supply sense line of injector group B is too low while the module expects the group to be powered. In practice the feed never reaches the injectors – a blown fuse, a relay that does not close, a broken supply wire or a grounded feed – or only the sense wire itself is grounded. In the first case the cylinders of group B receive no fuel and misfire or stay dead; in the second the engine may run normally. No publicly accessible manufacturer source documents P2C27; CARB requires out-of-range low checks of such circuits. GM's direct-injection logic, documented for the Saab 9-5 2.0T, disables an injector once its supply voltage is wrong for more than 1 s and stores a Type B fault. The high case is P2C28.
P2C27 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.3 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2C27
- Check engine light
- Misfire on several cylinders, rough idle
- Clearly reduced power or engine will not start
Common causes of P2C27
- Most likelyBlown fuse in the injector group B supply
- PossibleInjector relay not closing or burnt contacts
- PossibleSupply or sense wire shorted to ground
- Less likelyInternally shorted injector pulling the group supply down
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel injector group bWiring harnessECM
What each part of P2C27 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| C | Area: hybrid propulsion. |
| 27 | The exact fault in that area. |
What to do next
- Note P2C27 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2C27
What does P2C27 mean?
P2C27 means "Fuel Injector Group B Supply Sense Circuit Low". P2C27 reports that the voltage read back on the supply sense line of injector group B is too low while the module expects the group to be powered. It is a generic code, so it means the same on every make.
Is it safe to drive with P2C27?
Drive gently and only to a workshop. With P2C27 the car can go into limp mode (reduced power) to protect itself.
Will P2C27 fail an emissions test?
Yes, it can. P2C27 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2C27 to fix?
Difficulty: medium. A typical repair takes 0.3 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2C27 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.