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 car's computer has detected a problem with the part that helps one of the engine's cylinders start when it's cold. It's like when a light bulb doesn't work properly.
The P06BC code indicates that the engine control module (ECM) has detected a performance issue or range fault in the glow plug circuit for cylinder 4.
Glow plugs are used in diesel engines to heat the air in the cylinders and help the engine start in cold conditions. The ECM monitors the glow plug circuit for each cylinder. If it detects a problem with the electrical performance or range of the glow plug circuit for cylinder 4, it will trigger the P06BC code.
• Difficulty starting the engine in cold weather
• Engine misfires
• Illuminated check engine light
• Faulty glow plug for cylinder 4
• Damaged wiring or connectors in the glow plug circuit
• Faulty glow plug control module
Glow Plug: A device used to heat the air in a diesel engine's cylinder to help start the engine.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the glow plug and wiring for cylinder 4.
• Test the glow plug control module.
• Replace the faulty glow plug.
• Repair or replace damaged wiring or connectors.
• Replace the glow plug control module if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect glow plugs and wiring.
• Perform routine maintenance checks.
• Use high-quality diesel fuel.
Engine Performance
• Have a professional mechanic inspect the vehicle.
• Avoid driving in extremely cold conditions until repaired.
Check if the glow plug or related components are covered under the vehicle's powertrain warranty.
Glow plug issues are common in diesel engines, especially in colder climates where starting conditions are more challenging.
Moderate – It is advisable to address this issue soon, especially if you are in a cold climate, to avoid starting problems.
Driving with a malfunctioning glow plug can lead to increased emissions and potential engine damage.
• Engine cold start
• Ambient temperature below freezing
The glow plug for cylinder 4 is located on the engine block, typically on the passenger side of the engine.
Q: Can I drive with a P06BC code?
A: It's possible, but not recommended, especially in cold weather as it may lead to hard starting.
Q: How can I prevent glow plug issues?
A: Regular maintenance and using high-quality fuel can help prevent issues.
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Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.