P2237: Oxygen sensor current control circuit open (bank 1, sensor 1)
Electrical fault on one wire of the wideband oxygen sensor before the bank 1 catalyst. Usually the connector, the wiring or the sensor.
| Code | P2237 |
|---|---|
| System | Engine and transmission |
| Group | P22xx, NOx sensors, oxygen sensors and emissions |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P2237 means
Many modern engines use a wideband oxygen sensor ahead of the catalytic converter, which the ECU controls by sending it a small current. This code means the circuit that carries that current is open (broken) or not working. Without it, the ECU cannot measure the mixture properly and falls back on default values.
Most common causes
- Loose, dirty or corroded sensor connector
- Sensor wire broken or burnt by the exhaust
- Faulty wideband oxygen sensor
- Damaged sensor wires inside the loom (chafing)
- Fault in the ECU circuit (uncommon)
Symptoms
- Engine warning light on
- Higher fuel consumption
- Slightly rough idle
- Possibly weaker engine response
Can you drive with P2237?
With care You can drive, but without the sensor the mixture is not controlled precisely: consumption rises and the catalyst can suffer over time. Have it seen to soon.
Open the bonnetthe in-depth explanation
How to check it
Inspect the sensor lead from the exhaust to its connector for melted or chafed sections. With your reader, check whether bank 1 sensor 1 shows a live reading; if it is fixed or missing with the engine warm, that confirms the fault.
How to read and clear P2237 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P2237 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P2233 The signal circuit of heated lambda sensor 3 on bank 1 is shorted to its heater
- P2234 The signal circuit of heated lambda sensor 1 on bank 2 is shorted to its heater
- P2235 The signal circuit of heated lambda sensor 2 on bank 2 is shorted to its heater
- P2236 The signal circuit of heated lambda sensor 3 on bank 2 is shorted to its heater
- P2238 The lambda sensor positive current control (bank 1
- P2239 The lambda sensor positive current control (bank 1
- P223A The AdBlue heater E control has an electrical fault
- P223B The AdBlue heater F control has an electrical fault
- P2200 NOx sensor circuit fault (bank 1)
- P2201 NOx sensor circuit range or performance problem (bank 1)
- P2227 Barometric pressure sensor A range or performance problem
- P2228 Barometric pressure sensor A circuit low
What does code P2237 mean?
Many modern engines use a wideband oxygen sensor ahead of the catalytic converter, which the ECU controls by sending it a small current. This code means the circuit that carries that current is open (broken) or not working. Without it, the ECU cannot measure the mixture properly and falls back on default values.
Can you drive with P2237?
You can drive, but without the sensor the mixture is not controlled precisely: consumption rises and the catalyst can suffer over time. Have it seen to soon.
How do you clear P2237?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P2237 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
