P0677
Cylinder 7 Glow Plug Circuit
An electrical fault is present in the glow plug circuit for cylinder 7. The glow plug control module cannot drive this plug correctly — open circuit, short, or out-of-range resistance — so cylinder 7 is not pre-heated. On a cold start this causes hard starting, white smoke, and a misfire-like rough run until the engine warms. Causes: a failed glow plug, a broken supply lead to that plug, corrosion at the plug connector, or a faulty module output for cylinder 7.
An electrical fault is present in the glow plug circuit for cylinder 7. The glow plug control module cannot drive this plug correctly — open circuit, short, or out-of-range resistance — so cylinder 7 is not pre-heated. On a cold start this causes hard starting, white smoke, and a misfire-like rough run until the engine warms. Causes: a failed glow plug, a broken supply lead to that plug, corrosion at the plug connector, or a faulty module output for cylinder 7.
Common causes
- high
Glow plug element open
One of the most commonly reported causes for this code — check this first.
Typical part cost: $70-440
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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 P0677 mean?
P0677 means "Cylinder 7 Glow Plug Circuit". 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 P0677?
glow plug element open — 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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