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Diagnostic Procedure

NO. 18 COOLING SYSTEM CONCERNS-RUNS COLD - SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION) DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 DETERMINE IF MALFUNCTION CAUSE IS HVAC SYSTEM OR ENGINE
  • Is a customer complaint "Lack of passenger compartment heat" only?
Yes Inspect the A/C heater system.
Repair or replace the malfunctioning part according to the inspection results.
No Go to the next step.
2 VERIFY IDLE SPEED
  • Does the engine speed continue at fast idle?
Yes Perform the symptom troubleshooting "NO. 9 FAST IDLE/RUNS ON".
(See NO. 9 FAST IDLE/RUNS ON .)
No Go to the next step.
3 INSPECT ECT SENSOR SIGNAL
  • Access the ECT PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .)
  • Compare the ECT PID and low engine coolant temperature indicator light and high engine coolant temperature warning light operation.
  • Is the ECT PID value same as indicator/warning light readings?
Yes Go to Step 5.
No Go to the next step.
4 INSPECT ECT SENSOR Yes Repair or replace the malfunctioning part according to the inspection results.
No Perform the instrument cluster symptom troubleshooting "LOW ENGINE COOLANT TEMPERATURE INDICATOR LIGHT/HIGH ENGINE COOLANT TEMPERATURE WARNING LIGHT ILLUMINATES OR FLASHES CONTINUOUSLY".
(See LOW ENGINE COOLANT TEMPERATURE INDICATOR LIGHT/HIGH ENGINE COOLANT TEMPERATURE WARNING LIGHT ILLUMINATES OR FLASHES CONTINUOUSLY [INSTRUMENT CLUSTER] .)
5 DETERMINE IF MALFUNCTION CAUSE IS COOLANT CONTROL VALVE OR OTHER
  • Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST .)
    • ENG_CL_V_POS
      • ENG_CL_V_POS_R
  • Do the PID values indicate the following values when the PID ECT is 80 °C {176 °F} or more and while
    • ENG CL V POS: 59 °C {138 °F}
      • Difference between NG_CL_V_POS value and ENG_CL_V_POS_R value: Within 2°
Yes Go to Step 9.
No Go to the next step.
6 INSPECT COOLANT CONTROL VALVE Yes Repair or replace the malfunctioning part according to the inspection results.
No Go to the next step.
7 INSPECT COOLING FAN CONTROL SYSTEM OPERATION Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
8 VERIFY THAT NO FOREIGN MATTER IS IN ENGINE COOLANT Yes Replace the engine coolant.
(See ENGINE COOLANT REPLACEMENT .)
No Go to the next step.
9 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX .)
  • If the malfunction remains, inspect the related Service Bulletins and/or On-line Information and perform repair or diagnosis.
    • If the vehicle is repaired, troubleshooting is completed.
      • If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.