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2003
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Matrix XR, 4WD
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Repair and Diagnosis (Single Page)
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Engine Control System Self Diagnostics
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Diagnostic Tests
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DTC P0128: Thermostat Malfunction (Matrix Model)
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Possible Causes
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Possible Causes
Defective thermostat.
Defective cooling fan operation.
Defective cooling system.
Defective ECM.