P05BC

Stop-Start Mode Switch Circuit Open

Moderate severity

The driver-controlled switch that disables stop-start has an open control circuit - the ECU cannot read the driver preference and falls back to the default mode.

Common causes

Open in switch or harness
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $70-280
Pin pushed back out of connector body
Less common, but worth ruling out after the more likely causes.
low
Typical part cost: $70-280
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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 P05BC mean?

P05BC means "Stop-Start Mode Switch Circuit Open". It is a generic OBD-II code that points to a fault in the vehicle speed, idle control, auxiliary inputs.

What are the most common causes of P05BC?

open in switch or harness; pin pushed back out of connector body; cracked solder joint inside the module or sensor — 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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