What is P2237 : Engine Error code Causes Explained
The P2237 engine trouble code indicates an oxygen sensor signal circuit problem affecting fuel economy and emissions. Understanding its causes, symptoms, and solutions helps prevent engine performance difficulties and costly repairs.
How to Identify a DTCs Number
The DTC (Diagnostic Trouble Code) P2237 is an error related to the O2 (oxygen) sensor system. Specifically, it refers to O2 Sensor Positive Current Control Circuit/Open (Bank 1, Sensor 1). To identify this code by using an OBD-II scanner, which connects to your vehicle’s diagnostic port and retrieves error codes stored by the engine control module (ECM).
Understand, this trouble codes (DTCs) are 5 characters: 1 letter, 4 numbers. P-Powertrain indicates the fault code’s location. Generic or manufacturer-specific codes are indicated by the first digit. The second digit denotes the subsystem (7=transmission). The last two numbers describe the issue.
This error indicates that the upstream oxygen sensor (before the catalytic converter) is sensing a control circuit issue, such as an open circuit, broken wiring, or a failed sensor.
Causes of P2237 Error Code:
- Defective Oxygen Sensor (Bank 1, Sensor 1):
A faulty 02 sensor with a bad heater element causes inaccurate readings. - Damaged Oxygen Sensor Wiring:
Faulty 02 sensor wiring (frayed, corroded, or broken) can trigger this code. - Exhaust Leaks:
Exhaust leaks near the 02 sensor cause inaccurate readings, triggering P2237. - Faulty Engine Control Module:
Rarely, a faulty Engine Control Module can cause P2237, but it’s not the first suspect. - Vacuum Leaks:
Can lead to an incorrect air/fuel ratio, triggering the code.
Risk Level of P2237 Error Code:
A medium-risk level means the issue is not immediately critical but can impact engine performance, fuel efficiency, and emissions if left unresolved.
Driving with this issue for too long may lead to poor fuel economy, increased emissions, and potential long-term damage to engine components.
Common Car Brands Affected by P2237 Code:
The P2237 engine error code is commonly found in the following list.
- Ford
- Volkswagen
- Hyundai
- Honda
- Chevrolet
- Toyota
- Nissan
Video: P2237 Engine Error code
FAQ’s
What is the P2237 Engine Error Code?
The P2237 code indicates an issue with the oxygen (O2) sensor’s positive current control circuit in Bank 1, Sensor 1. It affects the air-fuel ratio readings, leading to incorrect engine adjustments.
What Causes the P2237 Error Code?
Common causes include a faulty O2 sensor, damaged wiring, corroded connectors, or issues with the engine control module (ECM). Contaminants like oil or coolant can also interfere with sensor function.
What is the Risk Level of the P2237 Code?
The risk level is medium. It can cause poor fuel efficiency, increased emissions, rough idling, or engine hesitation if left unresolved.
Which Vehicles are Affected by the P2237 Code?
This code is commonly found in vehicles from brands like Ford, Volkswagen, Hyundai, Honda, Chevrolet, Toyota and Nissan particularly those using advanced air-fuel ratio sensors.