P2240 Code: Bank 2 Sensor 1 Positive Current Circuit

What Does the P2240 Code Mean?

P2240 describes an open or faulty positive current control circuit associated with oxygen sensor Bank 2 Sensor 1. In the cited Volkswagen reference, the monitor is explicitly associated with pump-current control. This is an electrical monitor within the sensor-control system, not a direct instruction to replace the catalyst.

Wideband oxygen-sensor operation is more complex than watching a conventional switching voltage. A controller regulates sensor functions and interprets the resulting electrical behavior. Test-terminal roles, reference values and permitted methods depend on the exact sensor and controller. A familiar-looking connector is not enough to identify which terminal can safely be tested.

Bank 2 and Sensor 1 must be located from the engine information. Avoid assumptions based on the side of the car or connector accessibility. Once the right sensor is identified, separate its current-control wiring from heater wiring, reference circuits and any genuine mixture problem shown by independent evidence.

P2240 Symptoms, Severity, and Driving Safety

Arrange prompt diagnosis and follow the owner manual warning instructions. Avoid heavy load if engine operation is abnormal or mixture control remains uncertain. The code itself cannot predict catalyst damage or establish a safe mileage allowance.

P2240 Causes and the Evidence That Separates Them

The following are possible diagnostic branches, not a ranking of failure rates. Their relevance depends on the installed wideband oxygen-sensor circuit. Begin with the branch identified by the OEM decision tree and the complete code pattern.

If the warning followed sensor replacement, exhaust work or engine-harness repair, compare the timing with the original complaint. Recheck disturbed connections and part compatibility, but do not treat recent work alone as proof of causation. A component should earn replacement through a failed test.

Using UR1000 During P2240 Diagnosis

On supported vehicles, iCARZONE UR1000 retrieves accessible faults, available freeze frame and live data. Save the P2240 event before clearing it so the technician has the original evidence.

The official product page describes system diagnostics and bidirectional control. Confirm the exact VIN, controller, software and requested function before purchase. Every PID, active test or adaptation is not guaranteed on every vehicle.

On supported controllers, use UR1000 to preserve oxygen-sensor status, available lambda data, fuel trims and companion codes. Treat those as ECU-reported evidence. Physical circuit checks still require the correct equipment and the sensor-specific test method.

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Use the prescribed external equipment and current service information. A missing menu is a coverage question, not proof of failure. Price checked September 27, 2026; confirm the current offer on the product page.

How to Diagnose P2240 in 6 Steps

Use these six decisions alongside the VIN-specific procedure. Record conditions, measurements and comparison limits; never substitute another vehicle’s specification.

P2240 Quick Diagnostic Path

• 1

  Save the complete original event

  • Save all module faults, descriptions, suffixes, status and available freeze frame before clearing P2240. Preserve companion-code timing when investigating a shared condition.
  • Document engine temperature, load, sensor status, fuel-trim information and companion oxygen-sensor codes. Note whether the warning preceded sensor replacement, exhaust work or engine-harness repair. Do not reproduce an unsafe symptom.
• 2

  Locate the exact sensor and circuit

  • Confirm the engine-bank diagram, sensor position and complete OEM description. Identify all relevant terminal functions.
  • Do not treat passenger side, driver side or a generic wire color as a reliable bank or circuit identifier.
• 3

  Review the full fault pattern

  • Inspect heater, reference, supply, mixture and misfire records without merging their meanings.
  • Establish which faults are current and which appeared together before using fuel-trim behavior to choose a repair.
• 4

  Test the electrical path safely

  • Inspect heat-exposed wiring and connector integrity, then perform the prescribed isolated or powered measurements.
  • Do not use a test lamp, battery jumper or arbitrary ohmmeter test on a sensitive control terminal.
• 5

  Evaluate the sensor and controller separately

  • If external wiring passes, perform the sensor-specific test and only then follow any controller diagnostic branch.
  • A rich/lean label from invalid feedback does not replace physical engine diagnosis. Correct independent fueling or misfire faults when their own evidence supports it.
• 6

  Verify the repair under the right conditions

  • Repeat the failed check, complete any required setup and compare the result with the original evidence. An extinguished lamp alone is not verification.
  • Follow the OEM verification process and retain the final scan. Explain incomplete checks or remaining faults before releasing the vehicle.

How to Fix P2240 and Verify the Repair

Ask which finding supports each proposed P2240 repair. Separate confirmed defects from conditional work and retain the original and final reports.

If a new sensor does not resolve the fault, compare the returning code and status. Recheck compatibility, disturbed wiring and the original test evidence before replacing another sensor or the catalyst.

P2240 OEM Differences and DIY Limits

The 2014 Volkswagen Touareg reference lists P2240 for Bank 2 Sensor 1 positive current control and describes pump-current monitoring. That supports the circuit distinction here. Its engine-specific numerical thresholds are not universal and are intentionally not transferred into this guide.

Use the current service information for the exact engine and sensor technology. A conventional oxygen-sensor switching test, another bank’s pinout or an unrelated bulletin does not establish the correct procedure.

Related Diagnostic Code Guides

The following oxygen-feedback, heater, mixture and power guides distinguish neighboring fault types. Their bank/sensor locations and test methods do not replace the dedicated P2240 procedure.

For other stored faults, use the iCARZONE OBD-II fault-code center.

Frequently Asked Questions About P2240

Sources and Technical Review Notes

• Volkswagen Touareg Quick Reference Specification Book, February 2014 — P2240 bank/sensor and pump-current distinction in the listed engine tables; no universal numerical thresholds.
• Bosch Mobility — Wideband lambda sensor — Pump-cell and measurement-cell architecture; not a universal vehicle pinout or test limit.

iCARZONE

Technical sources checked September 27, 2026. This is a source-based diagnostic guide, not a report of a hands-on vehicle repair. Confirm component identification, monitor conditions, test limits and service applicability for the exact VIN. This guide makes no universal coverage or repair-outcome promise.