Short to voltage in the oxygen sensor signal or heater circuit wiring, often from chafed insulation against a power wire; Faulty oxygen sensor itself, with an internal short between the heater and signal circuits; Corroded or damaged connector pins at the sensor or engine computer, allowing voltage to bleed across circuits; Engine computer internal failure, though this is less common and should be diagnosed last; Aftermarket accessories or improper wiring repairs that inadvertently backfeed voltage into the sensor circuit; Water intrusion into the sensor connector causing a conductive path between pins

DTC codes / P22xx · Fuel and air metering (injector circuits) / P2242

P2242O2 Sensor Positive Current Control Circuit High (Bank 2 Sensor 1)

P2242 means the engine computer has detected that the current on the control circuit for the upstream oxygen sensor on bank 2 is higher than expected, indicating a short to voltage or a faulty sensor heater circuit. The computer monitors this current to ensure the sensor's heater and signal circuit are functioning within specification, and a high reading tells it that excessive current is flowing when it should not be.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Rough idle or engine misfire if the sensor is completely inoperative
Poor fuel economy due to incorrect air-fuel ratio feedback
Failed emissions test because the oxygen sensor monitor is not ready or the sensor is not switching
In rare cases, a dead battery or blown fuse if the short is severe and drains current
Possible hesitation or stumble during acceleration if the fuel mixture is affected

Common causes, most likely first

Short to voltage in the oxygen sensor signal or heater circuit wiring, often from chafed insulation against a power wire
Faulty oxygen sensor itself, with an internal short between the heater and signal circuits
Corroded or damaged connector pins at the sensor or engine computer, allowing voltage to bleed across circuits
Engine computer internal failure, though this is less common and should be diagnosed last
Aftermarket accessories or improper wiring repairs that inadvertently backfeed voltage into the sensor circuit
Water intrusion into the sensor connector causing a conductive path between pins

How to diagnose and fix it

Scan all modules for stored codes and freeze-frame data to confirm P2242 is the only oxygen sensor code and note the conditions when it set
Visually inspect the bank 2 sensor 1 wiring harness for chafing, burns, or signs of contact with hot exhaust components or power wires
Disconnect the sensor and inspect both sides of the connector for corrosion, water, or bent pins, then clean or repair as needed
Use a digital multimeter to measure voltage on the sensor control circuit with the key on and engine off, looking for unexpected battery voltage that would indicate a short
Check the sensor heater resistance and compare to specifications, and test for continuity between heater and signal pins to rule out an internal short
If wiring and connector are good, substitute a known-good sensor and clear codes to see if the code returns
As a last step, test the engine computer control circuit for a short to voltage with the computer disconnected, and replace the computer only if all other possibilities are eliminated

What a high current reading really means

A high current reading on the control circuit often points to a short to voltage rather than a failed sensor, so replacing the sensor without checking wiring can be a costly mistake.
The oxygen sensor heater circuit is powered by a fuse, and a shorted sensor can blow that fuse, causing multiple oxygen sensor codes to set at once and misleading you into thinking the computer is at fault.
Bank 2 sensor 1 is the upstream sensor on the bank that does not contain cylinder number one, so on V6 and V8 engines you must confirm which side is bank 2 before ordering parts.
This code can be set intermittently by water splashing onto a cracked sensor connector, so a wiggle test and visual inspection in wet conditions may be needed to reproduce the fault.
Some scan tools show oxygen sensor current in milliamps, and a reading that is high only at certain temperatures can indicate a heater element that shorts when hot, which a cold resistance test will miss.

Can I keep driving with P2242?

You can usually drive with this code because the engine will default to a safe fuel strategy, but avoid sustained heavy acceleration or towing until it is repaired. If the check engine light starts flashing or you notice rough running, stop driving and have it diagnosed promptly to prevent catalytic converter damage.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.