Audi DTC P1859 – Brake Switch Circuit Error Message from Engine Contr
DTC P1859 meaning on Audi
The Diagnostic Trouble Code (DTC) P1859 on an Audi indicates a Brake Switch Circuit error message from the Engine Control Module (ECM). This error occurs when the ECM detects a fault in the brake switch circuit, which is responsible for signaling the ECM when the brake pedal is pressed.
Audi DTC P1859 symptoms
Symptoms of DTC P1859 on an Audi may include:
- Malfunctioning brake lights
- Inability to shift out of park
- ABS or traction control warning lights illuminated on the dashboard
Audi DTC P1859 causes
Common causes of DTC P1859 on an Audi include:
- Defective brake switch
- Faulty wiring or connectors in the brake switch circuit
- ECM software issues
Audi DTC P1859 seriousness
While DTC P1859 may not directly affect the drivability of the vehicle, it is important to address this issue promptly as it can impact the safety features of the vehicle, such as brake lights and transmission interlock systems.
How to diagnose DTC P1859 on Audi
To diagnose DTC P1859 on an Audi, you can perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes stored in the ECM.
- Inspect the brake switch and its wiring for any visible damage or corrosion.
- Test the brake switch using a multimeter to ensure it is functioning properly.
- Check for any loose or damaged connectors in the brake switch circuit.
How to fix DTC P1859 on Audi
To fix DTC P1859 on an Audi, you can try the following solutions:
- Replace the faulty brake switch with a new one.
- Repair or replace any damaged wiring or connectors in the brake switch circuit.
- If the issue persists, reprogram or update the ECM software.
How to erase DTC P1859 on Audi
To erase DTC P1859 on an Audi, you can clear the fault codes using a diagnostic scanner or by disconnecting the vehicle’s battery for a few minutes. However, it is recommended to address the root cause of the issue before clearing the fault codes to prevent the error from reoccurring.
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