P2243: O2 Sensor Reference Voltage Circuit/Open Bank 1 Sensor 1
What Does P2243 Mean?
P2243 is a diagnostic trouble code indicating: O2 Sensor Reference Voltage Circuit/Open Bank 1 Sensor 1. This code relates to the powertrain system. It has been reported in NHTSA complaints across 1 different vehicle models.
Symptoms of P2243
- ⚠️ Check engine light illuminated
Common Causes
- 🔍 Blown head gasket
- 🔍 Sensor or control module malfunction
Real Owner Reports
From NHTSA complaint database — actual owner descriptions.
"Scanned for codes. Found P0303, P0299, and P2243 stored. Found coolant entering cylinder 3. Found excessive play in the waste gate rod and found A/F sensor is not responding. Needs head gasket. Vehicle starts up and runs rough. All alerts on alerts on dash on cust states check engine light on. Honda"
— Honda Accord owner, 02/17/2025
Source: NHTSA Complaints Database
Most Reported Vehicles for P2243
Based on NHTSA owner complaint data.
| # | Vehicle | Reports |
|---|---|---|
| 1 | HONDA ACCORD |
Frequently Asked Questions
Can I drive with this code?
Will this code clear itself?
How do I find the exact cause?
What To Do Next
Possible Fixes
- 🔧 Have the code scanned with a professional-grade scanner to read freeze frame data
- 🔧 Test the relevant sensor(s) with a multimeter before replacing
- 🔧 If DIY repair isn't feasible, get a diagnostic from a trusted mechanic ($50-150)
-
1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
-
2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
-
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.