Glow Plug #6 Circuit Failure
The P0676 code indicates a malfunction in the glow plug circuit for cylinder #6. Glow plugs are used in diesel engines to heat the combustion chamber for cold starts. This code is set when the powertrain control module (PCM) detects an open or short circuit in the glow plug or its wiring. Common causes include a faulty glow plug, damaged wiring or connector, or a failed glow plug control module. Symptoms may include hard starting, rough idle, and increased emissions, especially in cold weather.
01. Most Common Causes
- Faulty glow plug #6
- Open or shorted wiring in the glow plug circuit
- Corroded or damaged connector at glow plug #6
- Failed glow plug control module or relay
02. Symptoms You Will Notice
- Hard starting, especially in cold weather
- Rough idle or misfire on cylinder #6
- Check Engine Light illuminated
- Reduced fuel economy and increased emissions
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm code P0676 and check for other related codes.
Step 2: Visually inspect the glow plug #6 wiring and connector for damage, corrosion, or loose connections.
Step 3: Measure resistance of glow plug #6; typical spec is 0.5-2.0 ohms. Replace if open or shorted.
Step 4: Test voltage at the glow plug connector with key on; should be battery voltage. If not, check fuse, relay, and control module.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
You can drive short distances in mild weather, but starting will be difficult in cold conditions. Continued driving may cause excessive cranking, battery drain, and potential damage to the starter. It's best to repair promptly.
How much does it cost to fix?▼
Replacing a single glow plug typically costs $50-$150 including parts and labor. If the control module or wiring needs repair, costs can be higher.