LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2015 >> 3 SV, Standard Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> On-Board Diagnostic - Engine Controls (2 Of 6) >> DTC P0117 00: ECT Sensor No. 1 Circuit Low Input >> Notes
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0117 00: ECT Sensor No. 1 Circuit Low Input: Notes

DTC P0117:00 DETECTION CONDITIONS AND POSSIBLE CAUSES (SKYACTIV-G 2.0, SKYACTIV-G 2.5)

DTC P0117:00  ECT sensor No. 1 circuit low input 
DETECTION CONDITION 
  • The PCM monitors the ECT sensor No. 1 signal. If the PCM detects that the ECT sensor No. 1 voltage at the PCM terminal 1AK is below 0.2 V  for 5 s  , the PCM determines that the ECT sensor No. 1 circuit has a malfunction.

Diagnostic support note 
  • This is a continuous monitor (engine cooling system).
  • The check engine light illuminates if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA (Mode 2)/Snapshot data is available.
  • DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION 
  • Fixes the water temperature for the engine control at 40 °C {104 °F}  , and for the idle air control at 80 °C {176 °F}  .
  • Operates the cooling fan (high speed rotation).
  • Inhibits the fuel cut control during shift change.
POSSIBLE CAUSE 
  • Engine overheating (cooling system malfunction)
  • ECT sensor No. 1 connector or terminals malfunction
  • ECT sensor No. 1 malfunction
  • Short to ground in wiring harness between ECT sensor No. 1 terminal A and PCM terminal 1AK
  • PCM connector or terminals malfunction
  • ECT sensor No. 1 signal circuit and ground circuit are shorted to each other
  • PCM malfunction
G09794655Courtesy of MAZDA MOTORS CORP.
CAUTION:
  • Verify the malfunction symptom according to not only the PID value but also the symptom troubleshooting.
RELATED PIDS

Item (definition) Unit/Condition Definition Condition/Specification (Reference)
ECT °C, °F Engine coolant temperature
  • Displays ECT
V ECT sensor No. 1 voltage
  • ECT is 20 °C {68 °F}: Approx. 3.10 V
  • ECT is 40 °C {104 °F}: Approx. 2.16 V
  • ECT is 60 °C {140 °F}: Approx. 1.40 V
  • ECT is 80 °C {176 °F}: Approx. 0.87 V
  • ECT is 100 °C {212 °F}: Approx. 0.54 V