P2AE6: Intake Air O2 Sensor Negative Current Control Circuit Open Bank 1

P2AE6 points to an open negative current control line on the bank 1 intake air oxygen sensor. This is the shared return of pump and Nernst cell, which Bosch names virtual ground (IPN/VM, pin 2); Saab's 2010 9-5 shows about 2.5 V on it at ignition-on, a bias that lets the pump current change direction. For the exhaust analog P2251, Ford separates an open VM from an open pump lead: lambda still reacts to reference-current pulses, and with the Bosch CJ125 chip the fault sets when for 10 s the sensor voltage remains between 1.45 and 1.55 V. No manufacturer publishes P2AE6 for the intake sensor. With the return missing, neither cell has a defined reference, the oxygen value is lost and EGR runs without feedback. P2AE7/P2AE8 are low/high, P2AE3 the open pump lead, P2AEF bank 2.

Bank 1 is the side of the engine with cylinder 1. Inline engines only have this bank.

Symptoms

• Check engine light on
• EGR runs without oxygen feedback

Most likely causes

• Virtual-ground return lead (pin 2) broken
• Corroded or loose return contact in the plug
• Internal break of the common electrode in the sensor

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the wiring and connector of the sensor indicated
2. Check the continuity of the wire between the component and the control module.
3. Look for exhaust leaks
4. Check the signal in live data with the engine warm
5. Check the fuse and the heater resistance if the code mentions it
6. Replace the sensor if it has power and does not respond

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P2AE6 means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• A: Hybrid or air and fuel
• E6: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2AE6?

Yes, you can normally drive in moderation, but get it repaired soon: you will use more fuel and the catalytic converter can be damaged over time.

What causes code P2AE6?

The most common causes are: virtual-ground return lead (pin 2) broken; corroded or loose return contact in the plug; internal break of the common electrode in the sensor.

Related codes

• P2AE7Intake Air O2 Sensor Negative Current Control Circuit Low Bank 1
• P2AE8Intake Air O2 Sensor Negative Current Control Circuit High Bank 1
• P2AE3Intake Air O2 Sensor Pumping Current Circuit Open Bank 1
• P2AEFIntake Air O2 Sensor Negative Current Control Circuit Open Bank 2
• P2251O2 Sensor Negative Current Control Circuit/Open (Bank 1 Sensor 1)

Sources

• newtonnet.co.uk: fordobd2012
• saabwisonline.com: dtc p2237 p2239 p2243 p2251 or p2626
• bosch-motorsport.com: Data Sheet 69034379 Lambda Sensor LSU 4.9
• law.cornell.edu: 13 CCR 1968.2

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.