2006 Mazda MX-5 Miata BaseFACTORY OEM SERVICE PROCEDURE

DTC P0118: Notes

DETECTION CONDITION AND POSSIBLE CAUSE (DTC P0118)

DTC P0118 ECT sensor circuit high input
DETECTION CONDITION 
  • The PCM monitors the ECT sensor signal at PCM terminal 2AH. If the PCM detects the ECT sensor voltage is above 4.58 V  , the PCM determines that the ECT sensor circuit has malfunction.
Diagnostic support note 
  • This is a continuous monitor (Engine cooling system).
  • The MIL illuminates if the PCM detects the above malfunction condition during first drive cycle.
  • PENDING CODE is available if the PCM detects the above malfunction condition.
  • FREEZE FRAME DATA is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • ECT sensor malfunction
  • Connect or terminal malfunction
  • Open circuit in wiring harness between ECT sensor terminal A and PCM terminal 2AH
  • Short to power supply in wiring harness between ECT sensor terminal A and PCM terminal 2AH
  • Open circuit in wiring harness between ECT sensor terminal B and PCM terminal 2AY
  • PCM malfunction
G04317705Courtesy of MAZDA MOTORS CORP.
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