P2491: Exhaust Gas Recirculation Cooler Bypass Control Circuit High — Bank 2
What to do
As P2490 — wiring first, and mention whether cold starts have changed character.
What this code means
Bank 2's bypass control circuit reads high — the mirror of P2490, with the same one-mode-permanently consequence and the same cold-morning-or-nothing symptom split. A line stuck driving the actuator holds the flap against its spring, which way depending on the design; the companion position codes say where it stopped.
Likely causes
Start here
- Wiring shorted to voltage · moderate
- Open circuit in control wiring · moderate
Less common
- Control module driver failure · specialist
Symptoms
Components involved
Information, not instruction
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Community experience
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