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 is having trouble talking to the part that helps the engine start when it's cold. It's like when a light bulb isn't working right.
The P037D code indicates an issue with the glow plug sense circuit, which is responsible for monitoring the glow plugs used to heat the engine's cylinders for easier starting in cold conditions.
The glow plug sense circuit monitors the operation of the glow plugs in a diesel engine. If the engine control module (ECM) detects a problem with the signal from the glow plug sense circuit, it will trigger the P037D code. This could be due to an open circuit, short circuit, or other electrical issue.
• Difficulty starting the engine in cold weather
• Check Engine Light illuminated
• Rough idling when starting
• Faulty glow plug
• Damaged glow plug wiring
• Faulty engine control module (ECM)
Glow Plug: A device used to heat the air in a diesel engine's cylinder to aid in starting.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect glow plug wiring for damage or disconnection.
• Test the glow plugs for proper operation.
• Replace faulty glow plugs.
• Repair or replace damaged wiring.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$100 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect glow plug system.
• Keep electrical connections clean and tight.
• Service the vehicle according to the manufacturer's schedule.
Sensor Issue
• Have the vehicle inspected by a professional if the code persists.
• Avoid driving in extremely cold conditions until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on glow plugs and related components.
Glow plug circuit issues have been common in diesel engines, especially in older models where electrical connections can degrade over time.
Moderate – Address the issue to ensure reliable engine starting in cold weather.
Driving with a malfunctioning glow plug system can lead to starting issues and increased emissions.
• Cold engine start
• Normal operating temperature
Glow plugs are typically located in the cylinder head of the engine.
Q: Can I drive with a P037D code?
A: While you may be able to drive, it's best to address the issue to avoid starting problems, especially in cold weather.
Q: How do I know if my glow plugs are bad?
A: Symptoms of bad glow plugs include difficulty starting the engine, especially in cold weather, and rough idling.
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