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Home >> Suzuki >> 2002 >> XL-7 Base, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0118: Engine Coolant Temperature Sensor Circuit - High Input >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  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. On scan tool, select DATA LIST mode and observe ECT SENSOR parameter. If scan tool displays -40°F (-40°C), go to next step. If scan tool does not display -40°F (-40°C), problem is probably intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
  3. Turn ignition off. Disconnect ECT sensor 3-pin harness connector. ECT sensor is located at front of intake manifold. Check for poor terminal contact at ECT sensor harness connector. If poor terminal contact is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST . If no problem is found, go to next step.
  4. Measure voltage between ground and ECT sensor harness connector terminal No. 1 (Orange/Black wire). If voltage reading is 4-6 volts, go to step  8. If voltage reading is not as specified, go to next step.
  5. Check for open or short in Orange/Black 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.
  6. Turn ignition off. Disconnect ECM 26-pin harness connector C51-3. ECM is located under instrument panel, behind glove box. See Figure. Check for poor terminal contact at ECM harness connector C51-3. If poor terminal contact is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST . If no problem with wiring is found, go to next step.
  7. Substitute a known good ECM, and repeat DTC CONFIRMATION TEST . If DTC does not reset, testing is complete.
  8. Turn ignition off. Connect a fused jumper wire between ECT sensor harness connector terminals No. 1 (Orange/Black wire) and No. 3 (Gray/Yellow wire). Observe ECT SENSOR parameter on scan tool. If parameter displays 327°F (164°C), replace ECT sensor. After repair, repeat DTC CONFIRMATION TEST . If parameter does not display 327°F (164°C), go to next step.
  9. Check for open in Gray/Yellow wire between ECT sensor and ECM. See WIRING DIAGRAMS article. If problem is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST . If no problem with wiring is found, go to next step.
  10. Substitute a known good ECM, and repeat DTC CONFIRMATION TEST . If DTC does not reset, testing is complete.
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