Powertrain, generic (extended)

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

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

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.

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

Symptoms

  • Check engine light on
  • EGR runs without oxygen feedback

Repair estimate

DifficultyMediumDIY possible
Parts and labour€0–350
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

intake air o2 sensor b1wiring harnessecm

Related codes

P2AE7P2AE8P2AE3P2AEFP2251

References: newtonnet.co.uk, saabwisonline.com, bosch-motorsport.com, law.cornell.edu.