The P2245: O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1 refers to an issue where the oxygen (O2) sensor reference voltage circuit for Bank 1 Sensor 1 is reading a voltage lower than what is expected. This issue can be due to faulty wiring, a malfunctioning sensor, or connector issues, which may result in the sensor not being able to send accurate data to the engine control module, leading to improper air-fuel ratio adjustments.
P2245 – Quick Overview
Code | Information |
---|---|
Meaning | P2245: O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1 |
Is it serious? | Yes, as a low reference voltage can prevent the O2 sensor from functioning correctly, leading to poor air-fuel mixture control and increased emissions. |
Possible causes | – Low voltage in O2 sensor reference voltage circuit for Bank 1 Sensor 1 – Faulty O2 sensor – Wiring issues – Connector problems |
How to diagnose? | – Measure voltage in the O2 sensor reference voltage circuit for Bank 1 Sensor 1 – Test the sensor for proper operation – Inspect wiring and connectors for faults |
P2245 Meaning
The P2245: O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1 code indicates that the reference voltage supplied to the oxygen sensor in Bank 1 Sensor 1 is below the acceptable range. The reference voltage is essential for the sensor to operate correctly. If this voltage is too low, the sensor cannot provide accurate data regarding the oxygen levels in the exhaust, leading to incorrect adjustments of the air-fuel mixture, ultimately affecting engine performance and emissions.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to determine if there are any additional related codes. Other codes may provide context or indicate whether the issue is isolated or part of a larger problem. | OBD-II Scanner |
Measure Voltage in the O2 Sensor Reference Voltage Circuit | Use a multimeter to measure the voltage in the reference voltage circuit for Bank 1 Sensor 1. Compare your readings to the manufacturer’s specifications to verify whether the voltage is below the expected range. | Multimeter, Vehicle Service Manual |
Test the Sensor for Proper Operation | Test the oxygen sensor using a diagnostic tool to ensure it is functioning as expected. If the sensor itself is faulty, it may not be using the supplied voltage correctly and may need to be replaced. | Diagnostic Scanner, Multimeter |
Inspect Wiring and Connectors for Faults | Inspect the wiring and connectors associated with Bank 1 Sensor 1. Look for visible signs of damage such as frayed or broken wires, corrosion on terminals, or loose connections. Faulty wiring or connectors can cause a drop in reference voltage. Repair or replace any damaged components. | Flashlight, Safety Gloves |
Inspect the Connector Condition | Examine the sensor connector to make sure that it is securely connected and that there are no bent pins or corrosion affecting connectivity. A poor connection can result in low voltage being delivered to the sensor. | Flashlight |
Clear the Code and Test Drive | After addressing any identified issues, use an OBD-II scanner to clear the code. Conduct a test drive while monitoring the sensor performance to verify that the reference voltage has returned to normal and the problem is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure the P2245 code has not returned. If the code persists, further diagnostics will be needed to identify the underlying issue. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)