P0673

Cylinder 3 Glow Plug Circuit/Open

Glow plugs (diesel) Generic OBD-II High

What it means

P0673 is a diesel code meaning the control module detected an open (broken) circuit to the glow plug on cylinder 3. Glow plugs pre-heat the combustion chamber for cold starting, so a dead plug causes hard starts, rough running when cold, and extra smoke until the engine warms up.

High

Can I keep driving? Drivable once warm, but expect hard cold starts and rough cold running until the glow plug circuit is repaired.

Real-world scan data

Seen in

1,278

scans in the past year

Found in

0.2%

of scans

0.4%

of scans that found faults

Appears alongside · share of P0673 scans

P0672in 49.2% of scans

P0671in 44.1% of scans

P0674in 32.3% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Hard starting when the engine is cold
Rough running and shaking for the first minute after a cold start
White or grey smoke from the exhaust on cold start-up
Check-engine (or glow plug) light on

Common causes

Most likely first

Failed glow plug on cylinder 3 (open circuit)Likely
Open or shorted wiring to the cylinder 3 glow plugCommon
Corroded or loose glow plug connectorCommon
Faulty glow plug control moduleLess often

How to diagnose & fix

Work through it in order

Read freeze-frame data and confirm the fault is specific to cylinder 3.
Measure the resistance of the cylinder 3 glow plug — an open (infinite) reading means it is failed.
Inspect the wiring and connector from the control module to that glow plug for breaks or corrosion.
Replace the failed glow plug (and clean/repair the connection).
If the plug and wiring are good, test the glow plug control module. Clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0673?+

Yes, once the engine is running and warm it drives normally. The main effect is hard cold starting and rough cold idle, which worsens in cold weather.

Can I just clear P0673?+

It will come back until the open glow plug or its wiring is repaired. A single dead glow plug won't clear itself.

Read & clear P0673 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX