P2233 code meaning
O2 Sensor Signal Circuit Shorted to Heater Circuit (Bank 1 Sensor 3)
Powertrain system Generic code P22xx codes Check engine light
What P2233 means
P2233 is the heater-to-signal short for sensor 3 on bank 1, a third oxygen sensor that some engines fit after a second catalyst or between two catalyst bricks. No manufacturer documents this code publicly. GM's checks for the rear-sensor codes P2232/P2235 show how such a fault is normally caught: the signal leaps by more than 2 V within 0.04 s whenever the heater is switched off. Jaguar Land Rover's 2015 bulletin for the 3.0 supercharged V6, which carries three sensors per bank, lists many sensor 3 faults but none of this type. CARB requires circuit faults of every monitored oxygen sensor to be detected. P2236 is the bank 2 counterpart. A third sensor serves only monitoring, so the car drives normally with the warning lamp on.
P2233 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.4 to 1.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P2233
- Check engine light without noticeable driving change
- Emissions inspection failed because of the stored code
Common causes of P2233
- Most likelyInternal leakage between heater and sensing element of sensor 3
- PossibleSensor 3 wiring melted or chafed along the exhaust or underbody
- Less likelyCorroded underbody connector of the third sensor
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Oxygen sensor bank1 sensor3Oxygen sensor heaterOxygen sensor wiring
What each part of P2233 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). |
| 33 | The exact fault in that area. |
What to do next
- Note P2233 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 P2233
What does P2233 mean?
P2233 means "O2 Sensor Signal Circuit Shorted to Heater Circuit (Bank 1 Sensor 3)". P2233 is the heater-to-signal short for sensor 3 on bank 1, a third oxygen sensor that some engines fit after a second catalyst or between two catalyst bricks. It is a generic code, so it means the same on every make.
Is it safe to drive with P2233?
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 P2233 fail an emissions test?
Yes, it can. P2233 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 P2233 to fix?
Difficulty: medium. A typical repair takes 0.4 to 1.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2233 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.