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P1678 – Honda DTC

Honda DTC P1678 – FPTDR Signal Line Failure

DTC P1678 meaning on Honda

DTC P1678 on a Honda refers to a fault with the Fuel Pump Thermal Device Resistor (FPTDR) signal line. This diagnostic trouble code indicates a communication issue within the circuit that controls the fuel pump thermal device.

Honda DTC P1678 symptoms

  • Check Engine Light (MIL) illuminated
  • Engine may stall or have difficulty starting
  • Reduced engine performance

Honda DTC P1678 causes

  • Open or short circuit in the FPTDR signal line
  • Corrosion or poor connections in the wiring harness
  • Defective fuel pump thermal device resistor

Honda DTC P1678 seriousness

The seriousness of DTC P1678 lies in the potential for engine stalling or starting issues. Ignoring this fault can lead to further damage to the fuel pump system and affect the vehicle’s drivability.

How to diagnose DTC P1678 on Honda

  1. Use a scan tool to retrieve the DTC and freeze frame data
  2. Inspect the FPTDR signal line for continuity and shorts
  3. Check the wiring harness for corrosion or damage
  4. Test the fuel pump thermal device resistor for proper function

How to fix DTC P1678 on Honda

  1. Repair any open or short circuits in the FPTDR signal line
  2. Clean or repair any corroded connections in the wiring harness
  3. Replace the fuel pump thermal device resistor if faulty
  4. Clear the DTC and test drive the vehicle to ensure the issue is resolved

How to erase DTC P1678 on Honda

  1. Use a scan tool to clear the DTC from the vehicle’s memory
  2. If the fault has been repaired, the Check Engine Light should turn off
  3. Perform a final check to ensure the DTC does not return

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← All Honda Diagnostic Trouble Codes

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