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 circuit that controls the glow plug or heater indicator. It's like a light on your dashboard that tells you if the car's engine heater is working, and right now, it's not getting enough power.
The P037A code is triggered when the Engine Control Module (ECM) detects a low voltage condition in the glow plug or heater indicator control circuit.
The glow plug or heater indicator circuit is responsible for signaling the status of the glow plugs, which are used in diesel engines to help start the engine. A low circuit condition indicates that there is insufficient voltage or a potential short in the circuit, preventing the proper operation of the glow plug system.
• Check Engine Light is on
• Difficulty starting the engine in cold conditions
• Glow plug indicator light may not illuminate
• Faulty glow plug relay
• Damaged wiring or connectors in the glow plug circuit
• Faulty glow plug control module
Glow Plug: A device used in diesel engines to heat the air in the cylinders to ensure efficient starting.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the glow plug relay and control module for faults.
• Check wiring and connectors for damage or corrosion.
• Replace the faulty glow plug relay.
• Repair or replace damaged wiring or connectors.
• Replace the glow plug control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools (screwdrivers, pliers)
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Dodge Ram 2500
• Regularly inspect and maintain the glow plug system.
• Ensure all electrical connections are clean and secure.
• Replace glow plugs at recommended intervals.
Sensor Issue
• Have your vehicle inspected by a professional if you experience starting issues.
• Avoid using the vehicle in extremely cold conditions until repaired.
Check with your vehicle manufacturer to see if the glow plug system is covered under warranty.
This code is more common in diesel vehicles, particularly in colder climates where glow plugs are more frequently used.
Moderate – While the vehicle may still operate, it could have difficulty starting in cold conditions.
Operating a vehicle with this code may lead to starting issues, especially in cold weather, and should be addressed to avoid being stranded.
• Engine at ambient temperature
• Key in the 'On' position without starting the engine
The glow plug control module is typically located in the engine bay, near the engine block or firewall.
Q: Can I drive with a P037A code?
A: You can drive, but starting the vehicle might be difficult in cold weather, so it's best to fix the issue soon.
Q: How do I reset the P037A code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue persists, the code will return.
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