P1691 – Hyundai DTC

Hyundai DTC P1691 – Immobilizer system – antenna malfunction

DTC P1691 meaning on Hyundai

DTC P1691 for Hyundai refers to an immobilizer system antenna malfunction. This diagnostic trouble code indicates that there is an issue with the antenna used in the vehicle’s immobilizer system.

Hyundai DTC P1691 symptoms

Symptoms of DTC P1691 on a Hyundai may include:

  • Engine not starting
  • Immobilizer warning light illuminated on the dashboard
  • Intermittent starting issues

Hyundai DTC P1691 causes

Common causes of DTC P1691 on a Hyundai include:

  • Antenna wiring or connection issues
  • Antenna damage or corrosion
  • Faulty immobilizer antenna

Hyundai DTC P1691 seriousness

The seriousness of DTC P1691 on a Hyundai is moderate. While it may not directly affect the drivability of the vehicle, it can prevent the engine from starting, leading to inconvenience and potential immobilization of the vehicle.

How to diagnose DTC P1691 on Hyundai

To diagnose DTC P1691 on a Hyundai, follow these steps:

  1. Use a diagnostic scanner to retrieve the trouble codes.
  2. Inspect the immobilizer system antenna for any visible damage or corrosion.
  3. Check the antenna wiring and connections for any issues.
  4. Perform a continuity test on the antenna to check for proper functionality.

How to fix DTC P1691 on Hyundai

To fix DTC P1691 on a Hyundai, you can:

  1. Repair or replace any damaged antenna wiring or connections.
  2. Replace the immobilizer antenna if it is faulty.
  3. Clean any corrosion on the antenna or connections.

How to erase DTC P1691 on Hyundai

To erase DTC P1691 on a Hyundai, follow these steps:

  1. Use a diagnostic scanner to clear the trouble codes.
  2. Ensure the issue causing the DTC has been resolved.
  3. Perform a test drive to confirm the repair and check for any recurring codes.

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