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Home >> Suzuki >> 1999 >> Swift Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0118: Engine Coolant Temperature (ECT) Circuit High Input
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DTC P0118: Engine Coolant Temperature (ECT) Circuit High Input

NOTE: If DTC P0108, P0113, P0118, P0123 and/or P0450 are set together, Check PCM harness connector "B" terminal No. 9 (Green/Red wire on Esteem, or Light Green/Black wire on Swift) for an open circuit.
  1. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Select ECT parameter. If display reads -40°F (-40°C), go to next step. If display reading is not -40°F (-40°C), check for an intermittent problem. Go to INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off. Disconnect ECT sensor harness connector located near coolant outlet. Turn ignition on. Measure voltage between ground and Light Green/Red wire (Esteem) or Gray/White wire (Swift) of ECT sensor harness connector. If reading is 4-6 volts, go to next step. If reading is greater than 6 volts, check wire for short to battery power. If reading is less than 4 volts, check wire for an open. Repair as necessary. If wiring is okay, replace PCM.
  3. Turn ignition off. Disconnect PCM 16-pin harness connector "B". Check continuity between PCM 16-pin harness connector "B" terminal No. 9 and Green/Red wire (Esteem) or Gray/White wire (Swift) at ECT sensor harness connector. If continuity exists, go to next step. If continuity does not exist, check wire for an open or poor connection. Repair as necessary.
  4. Connect PCM harness connector. Turn ignition on. Using a fused jumper wire, jumper terminals of ECT sensor harness connector together. If display on scan tool reads 246°F (119°C), replace ECT sensor. If display is not 246°F (119°C), replace PCM.
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