Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the computer in your car has detected a problem with the electric circuit that controls the glow plug for cylinder number 7. Glow plugs are like little heaters that help the engine start when it's cold.
The P068D code indicates that the voltage in the glow plug control circuit for cylinder 7 is higher than expected.
The glow plug control module monitors the voltage and current in the glow plug circuits. If it detects a voltage level that is higher than the specified range for cylinder 7, it triggers the P068D code. This could be due to a short circuit or a malfunctioning control module.
• Check Engine Light is on
• Difficulty starting the engine in cold weather
• Rough idle
• Faulty glow plug
• Short circuit in the glow plug wiring
• Faulty glow plug control module
Glow Plug: A device used in diesel engines to heat the air in the cylinders to ensure proper combustion.
Control Module: An electronic component that controls various functions in the vehicle.
• Check the glow plug for cylinder 7 for proper resistance.
• Inspect the wiring and connectors for damage or corrosion.
• Test the glow plug control module for proper operation.
• Replace the faulty glow plug.
• Repair or replace damaged wiring or connectors.
• Replace the glow plug control module if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram
• Regularly inspect glow plug connections.
• Ensure proper maintenance of the electrical system.
• Use high-quality glow plugs.
Electrical Circuit Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid driving in extremely cold conditions until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on glow plug systems.
Glow plug circuit issues have been common in diesel engines, especially in older models or those with high mileage.
Moderate – While the vehicle may still run, starting issues can worsen, especially in cold weather.
Driving with a malfunctioning glow plug system can lead to increased emissions and potential engine damage.
• Engine must be cold.
• Ambient temperature should be below 10°C (50°F).
The glow plug for cylinder 7 is located on the engine block, typically on the right side of the engine in V8 configurations.
Q: Can I drive with a P068D code?
A: It's possible but not recommended, especially in cold weather, as it can lead to starting issues.
Q: How do I reset the Check Engine Light after repairs?
A: Use an OBD-II scanner to clear the code after ensuring the issue is fixed.
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