Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is saying there's a problem with the part that helps the engine start when it's cold. It's like when a flashlight doesn't turn on because the switch is stuck.
This code indicates that the voltage in the control circuit for the second glow plug control module is higher than expected.
The P06F8 code is triggered when the Powertrain Control Module (PCM) detects a high voltage condition in the control circuit for Glow Plug Control Module 2. Glow plugs are used in diesel engines to heat the air in the cylinders to ensure proper combustion during cold starts. A high control circuit voltage could be due to a wiring issue, a faulty glow plug control module, or a PCM fault.
• Difficulty starting the engine in cold weather
• Check Engine Light illuminated
• Poor engine performance
• Faulty glow plug control module
• Wiring issues such as short circuits or open circuits
• Faulty PCM (Powertrain Control Module)
PCM: Powertrain Control Module, the vehicle's main computer that controls engine and transmission functions.
Glow Plug: A device used in diesel engines to heat the air in the cylinders to aid in starting the engine.
• Use an OBD-II scanner to confirm the code and check for other related codes.
• Inspect the wiring and connectors for damage or corrosion.
• Test the glow plug control module for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty glow plug control module.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect and maintain the glow plug system.
• Ensure all electrical connections are clean and secure.
• Use high-quality replacement parts.
Sensor Issue
• Get the vehicle checked by a professional mechanic.
• Avoid driving in extremely cold conditions until repaired.
Check with the vehicle manufacturer for warranty coverage on emission-related components.
This code is commonly associated with diesel engines and is often reported in colder climates where glow plug systems are critical.
Moderate – Addressing this issue is important to ensure reliable engine starting and performance.
Ignoring this code may lead to increased emissions and potential engine damage.
• Engine cold start
• Ambient temperature below freezing
The glow plug control module is typically located near the engine block or attached to the cylinder head.
Q: Can I drive with a P06F8 code?
A: It's not recommended to drive for long periods with this code, especially in cold weather, as it can lead to starting issues.
Q: How do I reset the P06F8 code?
A: After repairs, the code can be reset using an OBD-II scanner, but ensure the issue is fixed to prevent recurrence.
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