P05F9
Stop-Start Status Signal Circuit
A general circuit fault on the stop-start status signal - the bus or hardwire that tells other modules whether the engine is auto-stopped or running.
A general circuit fault on the stop-start status signal - the bus or hardwire that tells other modules whether the engine is auto-stopped or running.
Common causes
- high
Open in signal line
One of the most commonly reported causes for this code — check this first.
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
See related trouble codes
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Frequently asked questions
What does P05F9 mean?
P05F9 means "Stop-Start Status Signal Circuit". 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 P05F9?
open in signal line — 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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