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Home >> Suzuki >> 2002 >> Esteem GL, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 1.6L >> Diagnostic Tests >> DTC P0118: Engine Coolant Temperature Sensor Circuit - High Input >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

NOTE: If DTC P1705 is also set, clear Transmission Control Module (TCM) DTCs after completing repair.
  1. If engine system check has been performed, go to next step. If engine system check has not been performed, go to A4: ENGINE SYSTEM CHECK  under SYSTEM TESTS.
  2. Turn ignition on. Using scan tool, observe ECT parameter. If parameter reads -40°F (-40°C), go to next step. If parameter does not read -40°F (-40°C), problem is probably intermittent. System is okay at this time. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
  3. Turn ignition off. Disconnect ECT sensor No. 1 3-pin harness connector. ECT sensor is located in thermostat housing. See Figure . Check for poor terminal contact at ECT sensor connector. If poor terminal contact is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST  . If no problem is found, leave harness connector disconnected and go to next step.
  4. Turn ignition on. Measure voltage between ground and ECT sensor harness connector terminal No. 1 (Light Green/Red wire). See WIRING DIAGRAMS article. Voltage should be 4-6 volts. If voltage is as specified, go to step  6 . If voltage is not as specified, check for poor connections in ECT circuits, also check for open or short to voltage in Light Green/Red wire between ECT sensor and ECM. If problem is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST  . If no problem is found, go to next step.
  5. Substitute a known good ECM, and repeat DTC CONFIRMATION TEST  . If DTC resets, go to next step. If DTC does not reset, testing is complete.
  6. Using a fused jumper wire, jumper together ECT sensor harness connector terminal No. 1 (Light Green/Red wire) and No. 3 (Green/Red wire). See WIRING DIAGRAMS article. Turn ignition on. On scan tool, observe ECT parameter. If parameter reads 246°F (119°C), replace ECT sensor. After repair, repeat DTC CONFIRMATION TEST  . If parameter is not 246°F (119°C), go to next step.
  7. Disconnect ECM 16-pin harness connector C20. ECM is located under instrument panel, behind glove box. See Figure . Check for poor, loose, corroded or damaged terminal connections in ECM harness connector C20. See Figure . If problem is found, repair as necessary. If no problem is found, substitute a known good ECM, and repeat DTC CONFIRMATION TEST  .
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