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Home >> Suzuki >> 2001 >> Grand Vitara JLS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0118: Engine Coolant Temperature (ECT) Sensor Circuit, High Input >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST . If DTC P0118 is set, go to next step. If DTC P0118 is not set, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off. Disconnect ECT sensor connector. Turn ignition on. Measure voltage between ground and ECT sensor harness connector terminal No. 1 (Orange/Black wire). If 4.5-5.5 volts exist, go to next step. If 4.5-5.5 volts do not exist, check Orange/Black wire for short to ground between ECT sensor and PCM 26-pin connector C51-3 terminal No. 22. See WIRING DIAGRAMS article. Repair as necessary and go to DTC CONFIRMATION TEST . If wire is okay, replace PCM and go to DTC CONFIRMATION TEST .
  3. 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). Turn ignition on. Measure voltage between ground and ECT sensor harness connector terminal No. 1 (Orange/Black wire). If less than .15 volt exists, go to step  5. If .15 volt or more exists, go to next step.
  4. Check for open in Gray/Yellow wire between ECT sensor and PCM 26-pin connector C51-3 terminals No. 20. See WIRING DIAGRAMS article. Repair as necessary and go to DTC CONFIRMATION TEST . If wire is okay, disconnect PCM 26-pin connector C51-3. Check for poor terminal contact at PCM 26-pin connector C51-3. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, replace PCM and go to DTC CONFIRMATION TEST .
  5. Check ECT sensor operation. See ENGINE SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. Replace as necessary and go to DTC CONFIRMATION TEST . If ECT sensor is okay, check for poor terminal contact at ECT sensor connector. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, replace PCM and go to DTC CONFIRMATION TEST .
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