P2277 code meaning
O2 Sensor Signal Biased/Stuck Rich (Bank 2, Sensor 3)
Powertrain system Generic code P22xx codes Check engine light
What P2277 means
P2277 is the rich-side counterpart of P2276: the third, post-catalyst sensor on bank 2 does not drop to a lean reading. On such layouts the check normally runs during a fuel cut, when the second catalyst must fill with oxygen before the sensor can respond, so a slow or fouled element shows up here. No manufacturer publishes a threshold for P2277 itself; Jaguar Land Rover lists it among the bank 2 post-catalyst sensor codes of the 2014 to 2016 3.0 supercharged V6 and replaces water-damaged sensors. For reference, VW tests the bank 1 twin P2275 against 0.15 V after 4500 mg of oxygen, and Ford fails a sensor whose lean peak never drops below 0.48 V. A shorted signal wire or oil and coolant fouling are further causes. P2273 is the fault at sensor 2; P0164 a voltage above range.
P2277 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.3 to 1.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P2277
- Malfunction indicator lamp on
- No noticeable change in driveability
Common causes of P2277
- Most likelyBank 2 third oxygen sensor contaminated or water-damaged
- Less likelySignal wire of sensor 3 touching a voltage source
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Oxygen sensor downstreamOxygen sensor wiring
What each part of P2277 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 2 | Area: fuel and air metering (injector circuit). |
| 77 | The exact fault in that area. |
What to do next
- Note P2277 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 P2277
What does P2277 mean?
P2277 means "O2 Sensor Signal Biased/Stuck Rich (Bank 2, Sensor 3)". P2277 is the rich-side counterpart of P2276: the third, post-catalyst sensor on bank 2 does not drop to a lean reading. It is a generic code, so it means the same on every make.
Is it safe to drive with P2277?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2277 fail an emissions test?
Yes, it can. P2277 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 P2277 to fix?
Difficulty: medium. A typical repair takes 0.3 to 1.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2277 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.