Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the car's system that helps it start in cold weather. It's like when a light on your toy doesn't work because the wires are mixed up.
The P037B code indicates that the voltage in the glow plug or heater indicator control circuit is higher than expected.
The P037B code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the glow plug/heater indicator control circuit. This could be due to a short circuit, faulty wiring, or a malfunctioning component within the circuit.
• Check Engine Light illuminated
• Difficulty starting the engine in cold conditions
• Engine runs rough when cold
• Faulty glow plug control module
• Wiring issues such as shorts or opens in the circuit
• Faulty glow plug relay
Glow Plug: A device used to preheat the air in a diesel engine to aid in starting.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to verify the code.
• Inspect the wiring and connectors related to the glow plug circuit.
• Test the glow plug control module for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the glow plug control module if faulty.
• Replace the glow plug relay if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect and maintain the glow plug system.
• Ensure electrical connections are clean and secure.
• Use high-quality replacement parts.
Sensor Issue
• Have a professional inspect the vehicle if unsure.
• Avoid driving in extremely cold conditions until repaired.
Check with the vehicle manufacturer for warranty coverage on emission-related components.
This code has been associated with diesel engines that rely on glow plugs for cold starting.
Moderate – It affects starting performance, especially in cold weather.
Driving with this code may lead to increased emissions and starting issues.
• Engine cold start
• Ambient temperature below freezing
The glow plug control module is typically located in the engine bay, near the engine block.
Q: Can I drive with a P037B code?
A: It's possible, but you may experience starting issues, especially in cold weather.
Q: How serious is the P037B code?
A: It's moderately serious as it affects engine starting and performance in cold conditions.
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