P2231Fuel & Air Metering

O2 Sensor Signal Circuit Shorted To Heater Circuit Bank 1 Sensor 1

P2231 means the upstream O2 sensor signal circuit on Bank 1 Sensor 1 is shorted to the heater circuit. This causes an inaccurate air-fuel signal, usually from a damaged harness or a failed sensor.

🚗 Yes, short-term, but expect an emissions test failure.

MEDIUM

severity

🎯 Top Causes, Ranked by Likelihood

#1Failed O2 sensor$60-$300

45%

Internal shorting between signal and heater circuits.

#2Wiring harness short$50-$300

35%

Chafed wiring shorts signal to the heater circuit.

#3Connector fault$50-$200

15%

Corroded or bent pins bridge the circuits.

#4ECM fault$300-$1000

Rarely, the module input fails.

🩺 Common Symptoms

Check engine light
Failed emissions test
Rough running or poor fuel economy
Possible rich or lean condition

💰 Repair Cost: DIY vs Shop

DIY Cost

$60-$300

Shop Cost

$150-$450

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P2231

1Inspect O2 sensor wiring for chafing and shorts

2Check the connector for bridged or corroded pins

3Test signal and heater circuits with a meter

4Replace the O2 sensor if confirmed

❓ Frequently Asked Questions

Can I drive with P2231?

Short-term yes, but it will fail emissions and hurt fuel economy.

How much to fix P2231?

Usually $150-$450 at a shop; DIY sensor is $60-$300.

What causes P2231 most often?

A failed O2 sensor or a chafed wiring harness.

🔗 Related Codes

P2232P2237P2238P0130P0135