Powertrain, generic (extended)

P2630 O2 Sensor Pumping Current Trim Circuit Low (Bank 2 Sensor 1)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2630 reports a trim input that is too low at the upstream wide-band probe of bank 2, the cylinder bank without cylinder 1. Ford's petrol summaries of 2020-23 set it only with NTK probes, where the sensor interface chip sees the resistor line open or grounded; the same chip check runs for about 10 s before a fault is stored. GM documented the L66 3.5 L V6, a Honda design, in 2005: the bank 2 label resistor must not stay above 4.7 V for 5 s while the probe heater is active, and that table also files this under the low code. No service bulletin naming P2630 was found. Since only one bank is affected, the other bank keeps normal closed-loop control. The open fault on this probe is P2629, the high fault P2631, bank 1 low P2627.

Likely causes

Resistor line of the bank 2 probe open or rubbed through to ground
Bank 2 upstream probe internally defective
Damaged or heat-affected connector near the exhaust

Symptoms

  • Check engine light
  • Bank 2 running in open loop
  • Fuel economy slightly worse

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

oxygen sensor bank2 sensor1sensor calibration resistoroxygen sensor wiring

Related codes

P2627P2629P2631P2240P0151

References: fordservicecontent.com, gsi.ext.gm.com, law.cornell.edu.