P0674low severityPowertrain
Cylinder 4 Glow Plug Circuit
on 2003 Audi A6 3.0L V6 · AWD
What this code means
The PCM detected a fault in the glow plug control circuit for cylinder 4. This can cause hard starting and rough running in cold conditions on diesel engines.
Symptoms
- Hard cold starting
- Rough idle when cold
- Glow plug warning light
Common causes
- Faulty glow plug cylinder 4
- Corroded glow plug wiring
- Bad glow plug control module
- Blown glow plug fuse
Diagnostic steps
- Scan for related glow plug codes
- Measure resistance of cylinder 4 glow plug
- Check wiring and connectors to glow plug
- Test glow plug control module output
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