P0678

Cylinder 8 Glow Plug Circuit/Open

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$22–67 (est.)

Symptoms

Difficulty starting a diesel engine in cold weather
Check Engine Light
White smoke on cold start
Unstable engine operation after starting
Glow plug indicator on the dashboard

Causes

Burnt-out glow plug for cylinder 8
Broken power wire
Oxidation or poor contact in the connector
GPCM module malfunction
Wiring damage

How to Fix

Read OBD-II error codes
Measure the resistance of the spark plug of cylinder 8 (standard: 0.5–2 Ohm)
Inspect the wiring and spark plug connector
Check the supply voltage at the spark plug terminal
Replace a faulty glow plug
If the error occurs again, check GPCM

Related codes

P0677 P0679 P068E P068F P0670