P1304 – OBD-II DTC

OBD-II DTC P1304 – Cylinder Head Overtemperature Protection Active

DTC P1304 meaning

DTC P1304 refers to a diagnostic trouble code indicating that the cylinder head overtemperature protection system is active. This code is triggered when the engine control module (ECM) detects that the temperature of the cylinder head has exceeded safe operating limits. The system is designed to prevent engine damage by reducing performance or shutting down certain functions to cool the engine.

DTC P1304 symptoms

Common symptoms associated with DTC P1304 may include:

• Engine overheating
• Loss of engine power
• Illuminated check engine light
• Unusual engine noises
• Increased coolant temperature readings

DTC P1304 causes

Several factors can lead to the activation of DTC P1304, including:

• Low coolant levels or leaks
• Faulty thermostat
• Malfunctioning water pump
• Blocked or damaged radiator
• Faulty temperature sensor
• Engine oil issues, such as low levels or contamination

DTC P1304 seriousness

DTC P1304 is a serious issue that should not be ignored. If the cylinder head temperature remains high, it can lead to severe engine damage, including warped cylinder heads, blown gaskets, or complete engine failure. Immediate attention is recommended to prevent costly repairs.

How to diagnose DTC P1304

To diagnose DTC P1304, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1304 code.
2. Check for any additional trouble codes that may provide more context.
3. Inspect the coolant level and look for leaks in the cooling system.
4. Examine the thermostat and water pump for proper operation.
5. Test the temperature sensor for accuracy and functionality.
6. Check the radiator for blockages or damage.
7. Inspect engine oil levels and quality.

How to fix DTC P1304 step-by-step instructions

To fix DTC P1304, follow these steps:

1. Address any coolant leaks by repairing or replacing damaged hoses, gaskets, or components.
2. Replace the thermostat if it is found to be faulty.
3. Ensure the water pump is functioning correctly replace it if necessary.
4. Flush and clean the radiator to remove any blockages.
5. Replace the temperature sensor if it is not providing accurate readings.
6. Change the engine oil if it is low or contaminated.
7. After repairs, clear the DTC using an OBD-II scanner and monitor the vehicle for any reoccurrence of the code.

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