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Home >> Suzuki >> 2001 >> Swift GA, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0125: Insufficient Coolant Temperature For Closed Loop Operation >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST . If DTC P0125 is set, go to next step. If DTC P0125 is not set, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  2. Check heater operation and coolant flow. If heater takes a long time to become effective, or coolant flows into radiator on cold start, remove thermostat for inspection. Replace as necessary and go to DTC CONFIRMATION TEST . If thermostat operates properly, go to next step.
  3. Drain coolant. Disconnect ECT sensor connector. Remove ECT sensor from thermostat housing. Measure resistance between ECT sensor terminals while it is immersed in a container of water. Heat water slowly and ensure resistance changes as specified. See Figure. Replace ECT sensor as necessary and go to DTC CONFIRMATION TEST . If resistance is as specified, check for high resistance or poor connection in ECT sensor circuit. Repair as necessary. If ECT circuit is okay, replace PCM and go to DTC CONFIRMATION TEST .
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