Powertrain, generic (extended)

P245A EGR Cooler Bypass Control Circuit/Open (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

The bypass lets cold-start EGR skip the cooler and is switched back to cooling once the engine is warm. P245A flags the bank 1 control circuit, usually as an open. GM's 2017 tables show both actuator types: on the Duramax with a DC-motor flap the controller sees a load resistance above 200 kOhm while the H-bridge is off and needs 160 failures in 200 samples, while the vacuum-switched version needs 24 of 30 samples with the flap commanded to cooling; both are Type B. Ford used P245A differently on its 2013 to 2015 6.7 L Power Stroke, as an intrusive check that fails when the gas temperature after the cooler moves by less than 3 °C per second after the flap switches; in 2023 that test carries P245B. Ford reflashed 2018 to 2019 Super Duty PCMs for P245A. Shorts are P245C and P245D, bank 2 is P248E.

Likely causes

Open wire or unplugged connector at the bypass actuator
Actuator motor or solenoid winding open
Control software needing an update (some Ford diesels)

Symptoms

  • Malfunction indicator lamp on
  • EGR cooler bypass no longer switching; possible P2457 or P24A5 as follow-up

Repair estimate

DifficultyMediumDIY possible
Parts and labour€30–700
Time0.5–3 h

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

Parts involved

egr cooler bypass valve b1

Related codes

P245BP245CP245DP24A5P248EP2457

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