P06C4

Symptoms

• Slightly difficult cold engine start
• Check Engine Light Is On
• White smoke from the exhaust pipe at low temperatures
• Unstable engine operation when warming up in cold weather
• Increased starter cranking time

Causes

• Wear of the heating element of the glow plug of cylinder 12
• Poor contact or oxidation in the spark plug connector
• Partial damage to control circuit wiring
• Incipient failure of the relay or spark plug control module
• Corrosion of the terminal on the spark plug itself

How to Fix

1. Read error codes, record frozen frame data
2. Measure the resistance of the glow plug of cylinder 12 (standard 0.5–2 Ohm)
3. Inspect the spark plug connector and terminal, clean from oxidation
4. Measure the current through the spark plug when warming up using current clamps
5. Replace the glow plug when a deviation in parameters is confirmed
6. Reset codes and check for errors after repair

Related codes

Error P06C4 by Vehicle Brand