Powertrain, generic (extended)

P2437 AIR System Air Flow/Pressure Sensor Circuit Low (Bank 2)

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P2437 reports a bank 2 secondary air pressure signal stuck below its valid range. Audi lists it for the 2017 R8 and R8 Spyder, where it often shows up together with P2436; the bulletin's remedy is a new bank 2 pressure sensor G610. GM's 2018 tables name P2437 as a blocking condition for the bank 1 sensor tests, so a low reading on either side halts the whole secondary air diagnosis. Electrically, the usual suspects are an interrupted signal line, contact with ground or no 5 V supply; GM's bank 1 sensor treats a voltage under about 5–6 % of the reference as faulty, which gives an idea of the scale. Driving is not affected, but the secondary air readiness stays open. P2438 is the high-side code.

Likely causes

Bank 2 pressure sensor failed (Audi R8 bulletin replaces G610)
Signal wire open or shorted to ground
5 V supply to the sensor missing

Symptoms

  • Check engine lamp
  • Secondary air tests on both banks suspended

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–500
Time0.5–2.5 h

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

Parts involved

air system flow sensor b2sai wiring

Related codes

P2432P2435P2436P2438

References: static.nhtsa.gov, gsi.ext.gm.com.