P1405 – Mazda DTC

Mazda DTC P1405 – DPFE Sensor Upstream Hose Off Or Plugged

DTC P1405 meaning on Mazda

DTC P1405 for Mazda indicates an issue with the DPFE (Differential Pressure Feedback EGR) sensor upstream hose being disconnected or obstructed.

Mazda DTC P1405 symptoms

  • Check Engine Light (CEL) illuminated on the dashboard
  • Decreased engine performance
  • Possible rough idling or stalling

Mazda DTC P1405 causes

  • Upstream hose disconnected from the DPFE sensor
  • Upstream hose clogged or blocked
  • DPFE sensor malfunction

Mazda DTC P1405 seriousness

The DTC P1405 code on a Mazda should not be ignored as it can lead to reduced engine performance and potential drivability issues.

How to diagnose DTC P1405 on Mazda

  1. Inspect the DPFE sensor and its upstream hose for any signs of damage or disconnection
  2. Check for any blockages or obstructions in the upstream hose
  3. Use a diagnostic scan tool to retrieve the trouble codes and data related to the DPFE sensor

How to fix DTC P1405 on Mazda

  1. Reconnect the upstream hose to the DPFE sensor if disconnected
  2. Clean or replace the upstream hose if it is clogged or blocked
  3. If the DPFE sensor is faulty, replace it with a new one

How to erase DTC P1405 on Mazda

  1. After fixing the underlying issue causing DTC P1405, use a diagnostic scan tool to clear the trouble codes
  2. Follow the tool’s instructions to erase the DTC P1405 code from the vehicle’s computer

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