Powertrain, generic (extended)

P2492 EGR Cooler Bypass Position Sensor Circuit (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

The position sensor tells the controller where the bank 1 cooler bypass flap actually is; position-controlled flaps cannot be regulated without it. P2492 is the general circuit code for that sensor, used when the fault cannot be classed as a short to ground or to the supply. No manufacturer documents P2492 publicly. GM's Duramax tables from 2017 and 2018 monitor the same analog sensor, but split the electrical faults into P2494 (below 1 % of the 5 V reference) and P2495 (above 99 %), both Type B; a separate learning check at key-off is P24C4. Without a valid feedback signal the controller usually stops closed-loop flap control, which can then also set P245B. Damaged wiring, a loose connector or a lost 5 V reference are the main suspects.

Likely causes

Damaged sensor wiring near hot exhaust parts
Loose or corroded connector at the bypass valve
5 V sensor supply missing or shared circuit shorted

Symptoms

  • Check engine light on
  • Bypass flap no longer position-controlled

Repair estimate

DifficultyMediumDIY possible
Parts and labour€30–600
Time0.5–3 h

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

Parts involved

egr cooler bypass position sensor b1

Related codes

P2493P2494P2495P2496P2497P24C4

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