Mazda DTC P1390 – Octane Adjust Shorting Bar Out or Circuit Open
DTC P1390 meaning on Mazda
DTC P1390 for Mazda indicates an issue with the Octane Adjust Shorting Bar Out or Circuit Open. This fault code is related to the engine’s ability to adjust ignition timing based on the detected octane level of the fuel being used.
Mazda DTC P1390 symptoms
Symptoms of DTC P1390 on a Mazda may include:
- Check Engine Light (MIL) illuminated
- Engine running rough or misfiring
- Reduced engine performance
Mazda DTC P1390 causes
Common causes of DTC P1390 on a Mazda include:
- Faulty octane adjust shorting bar
- Open circuit in the octane adjust system
- Wiring issues or poor connections
Mazda DTC P1390 seriousness
DTC P1390 should be addressed promptly as it can lead to poor engine performance and potential long-term damage if left unresolved. Ignoring this fault code may result in increased fuel consumption and emissions.
How to diagnose DTC P1390 on Mazda
To diagnose DTC P1390 on a Mazda, follow these steps:
- Use a diagnostic scanner to retrieve the fault code and freeze frame data
- Inspect the octane adjust shorting bar and related wiring for any visible damage
- Perform a thorough inspection of the octane adjust system components
How to fix DTC P1390 on Mazda
To fix DTC P1390 on a Mazda, consider the following:
- Replace the faulty octane adjust shorting bar if necessary
- Repair any open circuits in the octane adjust system
- Ensure all wiring connections are secure and free of corrosion
How to erase DTC P1390 on Mazda
To erase DTC P1390 on a Mazda, you can clear the fault code using a diagnostic scanner. After addressing the underlying issue causing the fault code, clear the code to reset the Check Engine Light.
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