P066E

Symptoms

• Difficulty starting a diesel engine in cold weather
• The Check Engine light comes on
• Increased starter cranking time
• White smoke from the exhaust pipe when starting
• Unstable engine operation after a cold start

Causes

• Short circuit of the glow plug control wire of cylinder 3 to ground
• Broken or damaged control circuit wiring
• Glow Plug Control Module (GPCM) Malfunction
• Faulty glow plug cylinder 3
• Oxidation or damage to connectors

How to Fix

1. Read error codes with an OBD-II scanner, capture freeze frame data
2. Inspect the wiring and connectors of the cylinder 3 glow plug and GPCM
3. Measure the voltage in the glow plug control circuit of cylinder 3
4. Check the resistance of the glow plug (normal: 0.5–2 Ohm)
5. Check wires for short circuit to ground and open circuit
6. If the wiring is in good condition - diagnostics and replacement of the GPCM or spark plug

Related codes

Error P066E by Vehicle Brand