P045C

EGR B Control Circuit Low

Moderate severity

EGR B drive line stuck low — short to ground. EGR mixes inert exhaust into intake to lower combustion peak temperature — too little raises NOx, too much causes misfires and rough running.

Common causes

Short to ground
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $130-880
Connector pins corroded - high contact resistance
Less common, but worth ruling out after the more likely causes.
low
Typical part cost: $130-880
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P045C mean?

P045C means "EGR B Control Circuit Low". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P045C?

short to ground; connector pins corroded - high contact resistance; harness chafing through insulation — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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