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Home >> Acura >> 2003 >> RSX Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Performance System Self-Diagnostics >> Diagnostic Tests >> DTC P0128: Cooling System Malfunction
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DTC P0128: Cooling System Malfunction

NOTE: If DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0300, P0301, P0302, P0303, P0304, P0335, P0336, P0500, P0501, P0505, P1106, P1107, P1108, P1128, P1129, P1259 or P1519, are stored at same time as DTC P0128, troubleshoot those DTCs first, then recheck for DTC P0128.
NOTE: DTC P0128 can occasionally be set when hood is opened while engine is running.
  1. Check engine coolant level. Refill if necessary, repair coolant leak. If coolant level is okay, go to next step.
  2. Turn ignition switch on. Check radiator fan operation. Ensure A/C is off. If radiator fan does not run continuously, replace thermostat. If radiator fan runs continuously, check radiator fan circuit, radiator fan switch circuit and radiator fan switch. See appropriate wiring diagram under ENGINE PERFORMANCE in WIRING DIAGRAMS. If circuits and switch are okay, update ECM/PCM or substitute with known-good ECM/PCM. If symptom goes away, replace original ECM/PCM.
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