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Home >> Mazda >> 2016 >> 6 Touring, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting - Engine Control System >> No. 9 Fast Idle/Runs On >> Diagnostic Procedure
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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}: 

ECT PID value is less than 82 °C {180 °F}: 
2 VERIFY PCM DTC 
Yes Go to the applicable DTC inspection.
(See DTC TABLE [SKYACTIV-G 2.5] .)
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 [SKYACTIV-G 2.5] .)

    • APP1
    • APP2
    • CPP (MTX)
    • CPP/PNP (MTX)
    • ECT
    • O2S11
    • O2S12
    • SHRTFT1
    • LONGFT1
  • Do the PIDs indicate the correct values under the malfunction condition?

    (See PCM INSPECTION [SKYACTIV-G 2.5] .)

Yes Go to the next step.
No APP1, APP2 PIDs are not as specified:
CPP PID is not as specified: (MTX)
CPP/PNP PID is not as specified: (MTX)
ECT PID is not as specified:
O2S11, SHRTFT1, LONGFT1 PIDs are not as specified:
O2S12 PID is not as specified:
Repair or replace the malfunctioning part according to the inspection results.
  • If the malfunction remains:
    • Inspect communication error between TCM and PCM. (ATX)
      • Repair or replace the malfunctioning part according to the inspection results if necessary.
    • Perform the "INTERMITTENT CONCERN TROUBLESHOOTING" procedure.

      (See INTERMITTENT CONCERN TROUBLESHOOTING [SKYACTIV-G 2.5] .)

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 [SKYACTIV-G 2.5] .)

  • Monitor the AC_REQ PID while turning on and off the air conditioner using the 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:

If the AC_REQ PID is always OFF:
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 2.5] .)
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.

If the problem remains, overhaul the engine.
11 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms.

    (See SYMPTOM DIAGNOSTIC INDEX [SKYACTIV-G 2.5] .)

  • 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.