P1401 – OBD-II DTC

OBD-II DTC P1401 – Glow Plug Monitor Fault (Bank #2)

DTC P1401 meaning

DTC P1401 refers to a fault in the glow plug monitor system for Bank #2 in diesel engines. This diagnostic trouble code indicates that the engine control module (ECM) has detected an issue with the glow plug operation or its monitoring system. Glow plugs are essential for starting a diesel engine, especially in cold conditions, as they preheat the combustion chamber to facilitate ignition.

DTC P1401 symptoms

Common symptoms associated with DTC P1401 may include:

• Difficulty starting the engine, particularly in cold weather
• Increased engine cranking time
• Rough idling or misfiring during initial startup
• Illumination of the check engine light (CEL)
• Decreased fuel efficiency

DTC P1401 causes

Several factors can lead to the triggering of DTC P1401, including:

• Faulty glow plug in Bank #2
• Malfunctioning glow plug relay
• Wiring issues, such as damaged or corroded connectors
• Faulty engine control module (ECM)
• Issues with the glow plug control circuit

DTC P1401 seriousness

DTC P1401 is considered a moderate to serious issue. While it may not cause immediate engine damage, it can lead to starting difficulties and increased emissions. If left unaddressed, it may result in further complications, such as damage to the glow plugs or the ECM, and can affect overall engine performance.

How to diagnose DTC P1401

To diagnose DTC P1401, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1401 code.
2. Inspect the glow plugs in Bank #2 for physical damage or wear.
3. Check the glow plug relay for proper operation.
4. Examine the wiring and connectors for signs of corrosion or damage.
5. Test the glow plug control circuit for continuity and proper voltage.
6. Clear the code and perform a test drive to see if the code reappears.

How to fix DTC P1401 step-by-step instructions

To fix DTC P1401, follow these steps:

1. Replace any faulty glow plugs in Bank #2.
2. Replace the glow plug relay if it is found to be malfunctioning.
3. Repair or replace any damaged wiring or connectors in the glow plug circuit.
4. Ensure the ECM is functioning correctly replace it if necessary.
5. Clear the DTC using an OBD-II scanner.
6. Test the vehicle to ensure the issue is resolved and the code does not return.

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