P06F9

Glow Plug Control Module 2 System Voltage

Moderate severity

Glow Plug Control Module 2 System Voltage: the control module has detected this fault condition. This affects diesel cold-start preheating.

Common causes

Supply voltage low
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $130-500
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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 P06F9 mean?

P06F9 means "Glow Plug Control Module 2 System Voltage". It is a generic OBD-II code that points to a fault in the computer & auxiliary output controls.

What are the most common causes of P06F9?

supply voltage low — 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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