By iCarsoft Official Store Technical Team, Automotive Diagnostics Editors · Updated September 7, 2026 · OEM technical references checked
Quick Answer
The P2240 code means o2 sensor positive current control circuit/open bank 2 sensor 1. It does not prove that the engine is running lean or rich solely from the word positive. Save the scan, identify the exact architecture, and test the physical and electrical paths before selecting a repair.
What Does the P2240 Code Mean?
P2240 is standardized as O2 Sensor Positive Current Control Circuit/Open Bank 2 Sensor 1. It names a monitored result, not a guaranteed failed part. The reporting module, suffix and companion faults determine the relevant test branch.
P2240 concerns the Bank 2 Sensor 1 wideband oxygen or air-fuel sensor positive-current control path. The Audi Q7 reference book describes an activity-check fault associated with an open pump-current circuit. This is separate from the heater and from a direct lean or rich mixture verdict.
Positive-current control is terminology for the wideband sensing circuit. It is not a direct statement that the exhaust is rich or lean, and it is not the sensor heater circuit. Keep those functions separate in the diagram so a valid heater test is not mistaken for proof that the current-control path works.
The Audi Q7 reference book lists P2240 for the Bank 2 Sensor 1 pump-current circuit on printed page 193, PDF page 202. Ford's code catalog corroborates the bank, sensor position and circuit/open classification. Test limits and circuit arrangements remain specific to the engine and sensor system.
For post-repair review, preserve the full code description and the tested bank and sensor position. Mark whether the recorded value is a controller-reported lambda, calculated current, or an external measurement. Those labels prevent a mixture-control observation from being mistaken for a direct electrical test of the positive-current circuit.
Separate P2240 from adjacent fault families
| Code | General description | Key distinction |
|---|---|---|
| P2237 | O2 positive-current control open B1S1 | Different bank. |
| P2241 | O2 positive-current control low B2S1 | Low classification, not the open monitor. |
| P2242 | O2 positive-current control high B2S1 | High classification. |
| P0050 | O2 heater control B2S1 | Heater wiring is a separate function. |
Record the complete P2240 description. The suffix, reporting module and companion faults can change the diagnostic path. Current manufacturer evidence governs when the queue wording conflicts.
P2240 Symptoms and Likely Causes
P2240 symptoms depend on fault status and the fallback strategy. Record what the driver and modules reported. A symptom list is not a parts list.
Save heater, current-control and mixture codes as separate evidence.
A fallback strategy may affect fueling; positive current does not by itself mean lean or rich.
Correlate the complaint with combustion and fuel-trim records.
Confirm the change rather than promising a universal symptom.
Practical cause-checking order
- Connection evidence: An incorrect, contaminated or heat-damaged B2S1 connector can interrupt its sensitive control circuit.
- Electrical path: An open pump-current/control path requires the correct wideband wiring diagram, not a generic narrowband voltage test.
- Supporting condition: Shared supply or controller-support problems need separate proof before replacing the exhaust sensor.
- Component evidence: The exact sensor is a candidate only after its circuit branch is isolated and tested.
- Final decision branch: A controller problem remains a late branch after correct sensor application, wiring and reference paths are verified.
Did P2240 appear after recent oxygen-sensor or exhaust service? Recheck disturbed connectors, grounds, hoses, fluids, part numbers and setup steps for the Bank 2 Sensor 1 positive-current control circuit. Record battery and software history; a post-repair code does not prove the new part is defective.
How Serious Is P2240, and Can You Drive?
Arrange diagnosis promptly. When the warning is steady, operation remains normal and the owner's manual permits it, a short light-load trip to a repair facility may be reasonable. Avoid demanding use until the Bank 2 Sensor 1 positive-current control circuit is understood. P2240 does not provide a universally safe distance.
Record temperature, load, speed, start state and recent service. Do not reproduce a severe symptom on public roads; another warning can make the situation more urgent.
Stop and arrange a tow if a flashing warning lamp, severe misfire, fuel odor or unsafe power loss occurs.
Cool the exhaust before access. Do not apply external voltage or use a test lamp across a sensitive wideband controller circuit. Stop driving for flashing MIL or severe misfire.
How to Diagnose P2240 in the Right Order
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Preserve oxygen, heater and mixture fault records
Save the complete oxygen/heater/fuel-trim code set and freeze-frame context before clearing. Keep the original status and operating conditions so the next test answers the failure that actually occurred. If the event is intermittent, record what changes before reconnecting parts or cycling power.
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Identify Bank 2 Sensor 1 on the exact engine
Identify Bank2 by the engine layout and Sensor1 by OEM exhaust position; do not infer left/right universally. Confirm the exact component designation, connector view, equipment version and test state. A generic code description cannot supply a pin location, terminal assignment or pass/fail value for a different engine.
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Inspect the correct sensor connector and routing
Inspect the B2S1 connector, routing and terminals for exhaust heat damage, contamination and wrong sensor/connector fit after service. Check the suspected area without disturbing unrelated components. Photograph damage, note which circuits share a connection, and retest after a controlled correction so cause and effect remain traceable.
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Test the specified pump-current and reference paths
Check the specified control/reference/pump-current circuit with approved terminal tools; keep heater, pump-current, Nernst/reference and negative-current paths distinct. Use the approved adapters and test instrument for the circuit. An unloaded continuity result can miss a fault that appears only during operation; an unsupported scan parameter is unavailable evidence, not a zero reading.
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Correlate valid wideband data with measured evidence
Evaluate supported wideband lambda/current evidence against operating conditions and the other bank where appropriate; a scan reading is not an independent circuit current measurement. Compare evidence from the controller with the appropriate independent physical test. A request or learned label does not establish that the connected system can perform its function under the failed conditions.
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Verify the repaired circuit and monitor outcome
Replace the exact correct sensor or repair the circuit only after isolating the failed branch; confirm closed-loop evidence and monitor outcome after repair. Document what passed after the repair, including the original failure condition and any required monitor or learning state. Do not call a cleared warning a verified result when its enabling conditions have not occurred.
Specifications are vehicle-specific. There is no universal voltage, resistance, current, pressure, waveform, timing, temperature, percentage, learned value or drive cycle for P2240. Test state, connector location and system design change what a valid value means. Use only specifications for the exact VIN and do not transfer the OEM example in this article to another application.
P2240 Repairs and Typical Costs
The correct P2240 repair follows the failed test. Wiring, a physical repair, a proven component, software and controller work are different outcomes. Do not replace an assembly from the generic code alone.
After installation, recheck connector seating, harness clearance, fluid or mechanical setup and every required learn. Bank 2 must be identified from the engine layout, and Sensor 1 from its specified exhaust position. Left and right depend on the engine and reference viewpoint. Confirm the exact replacement part and connector application; a sensor sold for a similar model can have a different circuit arrangement or calibration.
| Possible path | Current US estimate |
|---|---|
| Diagnosis and confirmation of Bank 2 Sensor 1 positive-current control circuit | VIN-specific quote |
| Verified connector, harness or supporting-system repair | VIN-specific quote |
| A component replacement supported by the failed test | VIN-specific quote |
| Required OEM setup and repeat-condition verification | VIN-specific quote |
There is no single national P2240 repair price because these rows are alternative outcomes. Ask for an itemized estimate showing diagnostic time, parts, labor, fluids, service-information access and verification. Location, taxes, related damage and warranty eligibility change the total. Do not add the rows together or authorize an assembly without the supporting failed test.
Using iCarsoft CR Eagle P for P2240
On a supported vehicle, iCarsoft CR Eagle P can retrieve accessible module faults, save available freeze frame, display ECU-provided live data and create a diagnostic report. For P2240, preserve the original evidence and compare related modules before clearing an erasable record.
Preserve the Bank 2 Sensor 1 positive-current control circuit evidence
iCarsoft CR Eagle P
Review supported codes and relevant live data together. Confirm the exact VIN, controller access, PIDs and any requested active test with iCarsoft before purchase; generic product capabilities do not guarantee a P2240-specific function.
Check current CR Eagle P price and availabilityCheck CR Eagle P compatibility by VINThe official product page describes full-system diagnostics, available freeze frame and live data, and supported bidirectional tests and ECU coding; availability varies with the vehicle, ECU and software. Active-test and coding availability varies by vehicle and ECU and requires VIN confirmation. Follow OEM prerequisites and stop for abnormal operation.
Know the measurement boundary. The scanner reports information supplied by the vehicle. It does not directly prove terminal tension, circuit load capacity, leakage, pressure, temperature, mechanical travel or internal condition in the Bank 2 Sensor 1 positive-current control circuit. It also cannot replace the manufacturer-approved wideband test equipment, suitable meter and protected terminal adapters when the OEM procedure requires them. Interpret commanded and reported values alongside measured evidence.
Verify the P2240 Repair
After repair, verify connectors, harness clearance, setup and controller supply. Save post-repair findings, then clear only erasable records through the approved procedure. Battery disconnection is not a repair.
Run the manufacturer's applicable verification conditions in a safe workshop or route. Compare the original operating state with current data for the Bank 2 Sensor 1 positive-current control circuit, and check current and pending faults in related modules. One clean start or idle period does not prove that every conditional monitor has completed.
If P2240 returns, compare its suffix, status, failure order and operating conditions with the saved baseline before replacing another part. Revisit the failed branch and inspect anything disturbed. Keep mechanical repair, monitor completion, readiness and local inspection eligibility as separate outcomes.
A permanent P2240 can remain immediately after a successful repair. If the vehicle stores it as a permanent DTC, a scan tool or battery disconnect cannot erase it. Once current and pending faults are absent, the OBD system removes the permanent record only after the applicable monitor reruns and passes.
Related Bank 2 Sensor 1 Positive-Current Control Circuit Code Guides
P2240 Frequently Asked Questions
Does P2240 mean the named component is bad?
No. P2240 describes o2 sensor positive current control circuit/open bank 2 sensor 1, not a confirmed part. It also does not prove that the engine is running lean or rich solely from the word positive. Test accessible wiring, supplies, grounds and supporting physical conditions, then follow the exact monitor tree. Replace a component only when its branch fails or an applicable OEM action specifically supports it.
What should I check first for P2240?
Save every module's codes and freeze frame before clearing. Confirm the full definition, suffix and VIN architecture. Then inspect recent oxygen-sensor or exhaust service, connectors and shared supplies. Those facts determine whether the next test needs the manufacturer-approved wideband test equipment, suitable meter and protected terminal adapters or a manufacturer-specific functional procedure.
Can I drive with the P2240 code?
Only consider a short light-load trip when operation is normal and the owner's manual permits it. Stop if a flashing warning lamp, severe misfire, fuel odor or unsafe power loss occurs. The code number cannot establish a safe mileage allowance, and another warning can make the situation more urgent.
Why did P2240 return after a part was replaced?
P2240 can return after an oxygen-sensor replacement if the wrong bank or sensor was serviced, the replacement has the wrong circuit specification, or the pump-current wiring and connector fault remains. Confirm the exact part and Bank 2 Sensor 1 location before repeating the approved circuit tests. A valid heater or lambda reading does not independently prove that the positive-current control path is healthy.
What should a P2240 repair estimate include?
A VIN-specific estimate is required because diagnosis may lead to wiring, a supporting physical repair, a verified component, software or a controller. Ask which failed test supports the quote and whether diagnosis, taxes, setup and post-repair verification are included.
Can CR Eagle P diagnose and clear P2240?
On a supported vehicle, CR Eagle P can organize available faults, freeze frame, live data and reports, and can clear erasable records after repair. Confirm exact ECU coverage. It cannot force-clear a permanent DTC or replace physical measurements for the Bank 2 Sensor 1 positive-current control circuit.
The iCarsoft Official Store Technical Team maintains the store's fault-code library. This guide organizes published manufacturer evidence and verified product information; it does not document a hands-on test of a particular vehicle or claim an individual engineer's review.
Technical and cost references
- 2014 Audi Q7 Quick Reference Specification Book. Audi lists the Bank 2 Sensor 1 pump-current circuit on printed page 193, PDF page 202.
- Ford 2014 OBD-II 5 Digit Code Interpretation. Ford corroborates the bank, sensor position and circuit/open classification.
- California Bureau of Automotive Repair — On-Board Diagnostic Test Reference. Permanent DTCs are removed by the vehicle after applicable verification, not by a scan-tool erase command.
Product information: Official iCarsoft CR Eagle P page.
Editorial note: General diagnostic education, not a substitute for the owner's manual, current VIN-specific service information or professional inspection. Test limits, procedures, coverage and costs vary. Related articles provide context; apply only the specifications and repair procedures that match the vehicle. No universal failure rate, repair price or outcome is implied.
