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Home >> Mazda >> 2017 >> CX-5 Grand Select, AWD >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (1 Of 5) >> DTC P0118-00: ECT Sensor Circuit High Input >> Diagnostic Procedure
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Diagnostic Procedure

DIAGNOSTIC PROCEDURE DESCRIPTION

STEP INSPECTION RESULTS ACTION
1 RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the FREEZE FRAME DATA/snapshot data on the repair order.
 - Go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 INSPECT ECT SENSOR CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the ECT sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 8.
No Go to the next step.
4 DETERMINE IF ECT SENSOR OR WIRING HARNESS MALFUNCTION Yes Replace the ECT sensor, then go to Step 8.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
5 INSPECT PCM CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 8.
No Go to the next step.
6 INSPECT ECT SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the ECT sensor and PCM connectors are disconnected.
  • Switch the ignition ON (engine off).
    NOTE:
    • Another DTC may be stored by the PCM detecting an open circuit.
  • Measure the voltage at the ECT sensor terminal A (wiring harness-side).
  • Is the voltage 0 V?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between ECT sensor terminal A and PCM terminal 1AK.
If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has a short to power supply.

Go to Step 8.
7 INSPECT ECT SENSOR CIRCUIT FOR OPEN CIRCUIT
  • Verify that the ECT sensor and PCM connectors are disconnected.
  • Switch the ignition off.
  • Inspect for continuity between the following terminals (wiring harness-side):
    • ECT sensor terminal A-PCM terminal 1AK
      • ECT sensor terminal B-PCM terminal 1AM
  • Is there continuity?
 Yes Go to the next step.
No Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • ECT sensor terminal A-PCM terminal 1AK
  • ECT sensor terminal B-PCM terminal 1AM

If there is a common connector:
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has an open circuit.

Go to the next step.
8 VERIFY DTC TROUBLESHOOTING COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .)
No DTC troubleshooting completed.
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