P0673
Cylinder 3 Glow Plug Circuit
An electrical fault is present in the glow plug circuit for cylinder 3. The glow plug control module cannot drive this plug correctly — open circuit, short, or out-of-range resistance — so cylinder 3 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 3.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Glow plug warning light on (often orange coil symbol)
- Hard cold start or no start in cold weather
- White smoke from exhaust during warm-up
Common causes
Ordered by how often each turns out to be the cause.
- Glow plug element openCommon
Parts involved
- Glow Plug
- Glow Plug Wiring
P0673 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.