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Diagnostic Procedure

NO. 9 FAST IDLE/RUNS ON (SKYACTIV-G 2.5T) DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 INSPECT COOLING SYSTEM FOR MALFUNCTION
Yes Go to the next step.
No ECT PID value is higher than 112°C {234°F}:
2 VERIFY PCM DTC
Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No Go to the next step.
3 VERIFY CURRENT INPUT SIGNAL STATUS
CAUTION:
  • While performing this step, always operate the vehicle in a safe and lawful manner.
  • When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later.
  • Access the following PIDs using the M-MDS: (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.5T)] .)
    • APP 1
    • APP 2
    • ECT
    • O2S11
    • O2S12
    • SHRTFT 1
      • LONGFT 1
  • Do the PIDs indicate the correct values under the trouble condition? (See PCM INSPECTION [SKYACTIV-G 2.5T] .)
Yes Go to the next step.
No APP 1, APP 2 PIDs are not as specified:
4 DETERMINE IF MALFUNCTION CAUSE IS A/C REQUEST SIGNAL OR OTHER
  • Access the AC_REQ PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.5T)] .)
  • Monitor the AC_REQ PID while turning on and off the air conditioner with switch on the control panel.
  • Does the AC_REQ PID value change from on to off according to switch control panel?
Yes Go to the next step.
No If the AC_REQ PID is always ON:
5 DETERMINE IF MALFUNCTION CAUSE IS DRIVE-BY-WIRE CONTROL SYSTEM OR OTHER
  • Will the engine run smoothly at part throttle?
Yes Go to Step 7.
No Go to the next step.
6 INSPECT DRIVE-BY-WIRE CONTROL SYSTEM OPERATION
Yes Visually inspect the throttle body (damage/scratching).
  • If there is any malfunction:
    • Repair or replace the malfunctioning part according to the inspection results.
  • If there is no malfunction:
    • Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
7 INSPECT FUEL INJECTOR OPERATION
Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
8 INSPECT HIGH PRESSURE FUEL PUMP
Yes Replace the high pressure fuel pump.
(See HIGH PRESSURE FUEL PUMP REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to the next step.
9 INSPECT CRUISE CONTROL SYSTEM
  • Inspect the operation of cruise control system.
  • Does the cruise control system work properly?
Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
10 INSPECT INTAKE-AIR SYSTEM FOR AIR LEAKAGE
  • Inspect for leakage in intake-air system.
  • Is there any leakage?
Yes Repair or replace the malfunctioning part according to the inspection results.
No Injector driver malfunction.
11 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.5T] .)
  • If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair 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.