P2AE9 Intake Air O2 Sensor Pumping Current Trim Circuit Open Bank 2

P2AE9 is the bank 2 version of the open trim circuit: the line from the ECM to the calibration resistor of the second intake air oxygen sensor has no continuity. A separate sensor for bank 2 only makes sense where each cylinder bank draws its charge or EGR through its own path; nobody has published a vehicle that uses P2AE9. The logic follows the exhaust analog P2629, which Ford sets for Bosch probes when the pumping current in air remains too high during a fuel cut-off event; Saab rates the bank 1 twin P2626 as Type B. As the Bosch datasheet explains, the resistor in the plug fixes the sensor's characteristic curve, so a broken trim lead leaves the reading of that bank uncalibrated. A pin pushed back in the connector is a frequent finding. P2AEA/P2AEB are low/high, P2AE0 bank 1.

Likely causes

Symptoms

• Check engine light on
• EGR on bank 2 reduced or without feedback

Repair estimate

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

Parts involved

Related codes

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