DTC P0125 & DTC P0128 Kia Optima I рестайлинг

Code Definition

1. DTC P0125: Excessive Time To Enter Closed Loop
2. DTC P0128: Coolant Thermostat Stuck Open

Note. Before performing any diagnostic test, refer toWARNINGS, CAUTIONS and NOTES in DIAGNOSTIC TESTS .

Note. Testing individual components does not isolate shorts or opens. Perform all voltage tests using a Digital Volt-Ohmmeter Meter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter to isolate wiring harness shorts or opens.

Diagnostic Aids

DTC P0125 and P0128 will set when engine coolant temperature at engine start takes longer than a predetermined amount of time. Also when after engine start-up, elapsed time before feedback operation is initiated is too long (engine coolant temperature sensor input is insufficient for closed loop operation). Check for following possible problems

1. Thermostat stuck open.
2. Misplaced, loose or corroded ECT sensor and Engine/Transaxle Control Module (E/TCM) or Engine Control Module (ECM) connectors or terminals.
3. Poor connections between ECT sensor and E/TCM or ECM.
4. Faulty ECT sensor.