P068D

Cylinder 7 Glow Plug Control Circuit High

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$17–278 (est.)

Symptoms

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

Causes

Control wire short circuit to power
Open ground circuit
GPCM module malfunction
Damage to wiring or connectors
Internal ECU fault

How to Fix

Read OBD-II codes
Inspect the wiring and connectors of cylinder 7 spark plug and GPCM
Measure the voltage in the control circuit
Check the ground circuit for open circuit
Check the wire for short to power
If serviceable - diagnostics and replacement of GPCM or ECU

Related codes

P068C P0677 P066B P0670