P2247: O2 Sensor Reference Voltage Circuit/Open (Bank 2 Sensor 1)

P2247 is the bank 2 version of P2243: the Nernst-cell reference line of the upstream wide-band sensor on the second cylinder bank is open. Ford's summaries trip it on Bosch sensors after 10 s outside 0.2-4.7 V and on NTK sensors via the interface chip, replacing the older P0150. VW's 2014 Touareg book names it an open Nernst-voltage circuit with limits of 0.25 and 4.80 V, while GM's 2005 V6 tables call it Type B. Field cases include Honda bulletin 14-002 (2010-11 V6 models, broken sensor tip, usually with P0430), Jaguar Land Rover LTB00671 (2014-16 3.0 supercharged V6, water shock) and a 2025 Ram 1500 3.0 engine software update (FCA 18-071-26). P2243 is bank 1, P2249/P2250 the low/high faults, P2254 the open ground line on bank 2.

Bank 2 is the side without cylinder 1, so it only exists on V or boxer engines. Sensor 1 is the oxygen sensor before the catalytic converter.

Symptoms

• Check engine light
• Higher fuel consumption from open-loop fuelling on bank 2
• Catalyst efficiency code P0430 if a sensor fragment damaged the converter

Most likely causes

• Broken reference voltage (Nernst cell) wire or loose pin on the bank 2 sensor
• Cracked element or broken sensor tip after thermal shock
• Engine software that sets the code falsely (update for some models)

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the wiring and connector of the sensor indicated
2. Check the continuity of the wire between the component and the control module.
3. Look for exhaust leaks
4. Check the signal in live data with the engine warm
5. Check the fuse and the heater resistance if the code mentions it
6. Replace the sensor if it has power and does not respond

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P2247 means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• 2: Fuel injection
• 47: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2247?

Yes, you can normally drive in moderation, but get it repaired soon: you will use more fuel and the catalytic converter can be damaged over time.

What causes code P2247?

The most common causes are: broken reference voltage (Nernst cell) wire or loose pin on the bank 2 sensor; cracked element or broken sensor tip after thermal shock; engine software that sets the code falsely (update for some models).

Related codes

• P2243O2 Sensor Reference Voltage Circuit/Open (Bank 1 Sensor 1)
• P2248O2 Sensor Reference Voltage Performance (Bank 2 Sensor 1)
• P2249O2 Sensor Reference Voltage Circuit Low (Bank 2 Sensor 1)
• P2250O2 Sensor Reference Voltage Circuit High (Bank 2 Sensor 1)
• P2240O2 Sensor Positive Current Control Circuit/Open (Bank 2 Sensor 1)
• P2254O2 Sensor Negative Current Control Circuit/Open (Bank 2 Sensor 1)
• P0150O2 Sensor Circuit Bank 2 Sensor 1
• P0430Catalyst System Efficiency Below Threshold Bank 2

Sources

• newtonnet.co.uk: fordobd2012
• static.nhtsa.gov: MC 10074008 2280
• gsi.ext.gm.com: 2005file14
• static.nhtsa.gov: MC 10129824 9999

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.