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 system that helps start the engine when it's cold. It's like when a heater doesn't turn on because there's a problem with the switch.
The P0670 code indicates an issue with the electrical circuit that controls the glow plug module, which is used to help start diesel engines.
The P0670 code is triggered when the Engine Control Module (ECM) detects an open circuit or a malfunction in the glow plug control module circuit. This module is responsible for pre-heating the glow plugs to aid in starting the engine, especially in cold conditions.
• Difficulty starting the engine, especially in cold weather
• Engine runs rough for a short period after starting
• Check Engine Light illuminated
• Faulty glow plug control module
• Open or shorted wiring in the glow plug circuit
• Poor electrical connection at the glow plug control module
Glow Plug: A device used to preheat the air in a diesel engine to aid in starting.
Control Module: An electronic component that manages specific functions in a vehicle.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors to the glow plug control module.
• Test the glow plug control module for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the glow plug control module if faulty.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Dodge Ram 2500
• Regularly inspect and maintain the vehicle's electrical system.
• Keep the battery and charging system in good condition.
• Ensure proper engine maintenance, especially in cold climates.
Engine Performance
• Address the issue promptly to avoid starting problems.
• Consult a professional mechanic if unsure about repairs.
Check with the vehicle manufacturer for specific warranty coverage related to the glow plug system.
The P0670 code has been a common issue in diesel engines, especially in older models, due to wear and tear on electrical components.
Moderate – While the vehicle may still operate, it can lead to starting issues, particularly in cold weather.
Driving with this code may lead to increased emissions and potential starting issues. It is advisable to address the problem to ensure safe and efficient vehicle operation.
• Engine at ambient temperature
• Use of diagnostic tools to verify circuit integrity
The glow plug control module is typically located in the engine bay, near the engine's intake manifold or cylinder head.
Q: What happens if I ignore the P0670 code?
A: Ignoring this code can lead to starting difficulties, especially in cold weather, and may cause further engine performance issues.
Q: Can I drive my car with a P0670 code?
A: While you can drive the car, it's advisable to fix the issue soon to prevent starting problems and ensure optimal engine performance.
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