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Symptom Troubleshooting [Engine Control System [Mzi 3.7 V6]]: Other Mazda 6 GJ

Testing & Diagnostics 4 illustrations ~1667 words

NO.1 MELTING OF MAIN OR OTHER FUSES [MZI 3.7 V6]

1 MELTING OF MAIN OR OTHER FUSES [TROUBLESHOOTING HINTS] Inspect condition of fuse

Scheme 122

Scheme 122: NO.1 MELTING OF MAIN OR OTHER FUSES [MZI 3.7 V6]
Scheme 122: NO.1 MELTING OF MAIN OR OTHER FUSES [MZI 3.7 V6]
Damaged fuseRelated wiring harness
MAINMAIN fuse BTN fuse ROOM fuse FAN fuse IG KEY2 fuse ENG+B fuse
BTNBTN fuse ROOM fuse
ROOMROOM fuse DLC-2
FANFAN fuse Fan control module relay
IG KEY2IG KEY2 fuse Starter relay
ST SIGST SIG fuse PCM Starter relay
FUEL PUMPFUEL PUMP fuse Fuel pump unit
ENG INJENG INJ fuse PCM Fuel injector No.1 Fuel injector No.2 Fuel injector No.3 Fuel injector No.4 Fuel injector No.5 Fuel injector No.6
ENGINE IGENGINE IG fuse PCM Fuel pump relay
ENG+BENG+B fuse PCM Canister vent solenoid valve Generator (IC regulator)
PCMPCM fuse Brake switch No.2 PCM
ENGINEENGINE fuse HO2S heater (LH) HO2S heater (RH) A/F sensor heater (LH) A/F sensor heater (RH) OCV (LH) OCV (RH)
IGIG fuse Ignition coil No.1 Ignition coil No.2 Ignition coil No.3 Ignition coil No.4 Ignition coil No.5 Ignition coil No.6
ENGINE2ENGINE2 fuse MAF/IAT sensor Purge solenoid valve

NO.2 MIL ILLUMINATES [MZI 3.7 V6]

2MIL ILLUMINATES
DESCRIPTIONThe MIL is illuminated incorrectly.
POSSIBLE CAUSEThe PCM illuminates for emission-related concern. (DTC is stored in PCM.) Instrument cluster malfunction NOTE: If the MIL blinks at steady rate, misfire condition could possibly exist.
NOTE
If the MIL blinks at steady rate, misfire condition could possibly exist.

NO.3 WILL NOT CRANK [MZI 3.7 V6]

3 WILL NOT CRANK DESCRIPTION The starter does not work. POSSIBLE CAUSE Open circuit between ignition switch and starter Starter relay No.2 malfunction Open or short circuit in wiring harness between keyless control module and starter relay No.2 (with advanced keyless entry and push button start system) Low or dead battery Charging system malfunction Starter malfunction Seized/hydrolocked engine, drive plate Immobilizer system and/or circuit malfunction Immobilizer system operating properly. (Ignition key is not registered.) Advanced keyless entry and push button start system malfunction (with advanced keyless entry and push button start system) TR switch malfunction

Scheme 123

Scheme 123: NO.3 WILL NOT CRANK [MZI 3.7 V6]
Scheme 123: NO.3 WILL NOT CRANK [MZI 3.7 V6]

NO.4 HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK [MZI 3.7 V6]

4HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK
DESCRIPTIONThe starter cranks engine at normal speed but engine requires excessive cranking time before starting. The battery is in normal condition.
POSSIBLE CAUSEVacuum leakage Poor fuel quality Air leakage or restriction in intake-air system Low or dead battery Charging system malfunction PCM DTC is stored. Engine overheating Purge solenoid valve malfunction MAF sensor contamination Incorrect MAF sensor ground voltage Improper operation of drive-by-wire control system Restriction in exhaust system Open circuit in PCM ground circuit Ignition coil related circuit malfunction Erratic signal to ignition coil Spark plug malfunction Erratic signal from CKP sensor Erratic signal from CMP sensor Inadequate fuel pressure Open or short circuit in fuel pump and related wiring harness Fuel pump mechanical malfunction Fuel line clogged Pressure regulator malfunction (built-in fuel pump unit) Fuel leakage from fuel system PCV valve malfunction Starting system malfunction Electrical connector loose or terminal poor contact WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.5 ENGINE STALLS-AFTER START/AT IDLE [MZI 3.7 V6]

5ENGINE STALLS-AFTER START/AT IDLE
DESCRIPTIONEngine stops unexpectedly.
POSSIBLE CAUSEVacuum leakage Air leakage from intake-air system parts Air cleaner restriction Poor fuel quality Electrical connector disconnection Throttle valve restriction or clogged PCM DTC is stored. No battery power supply to PCM or poor ground Erratic signal to PCM APP sensor or related circuit malfunction TP sensor or related circuit malfunction Improper operation of drive-by-wire control system Restriction in exhaust system No signal from CKP sensor due to sensor, related wire or wrong installation Ignition coil or related circuit malfunction Spark plug malfunction Fuel leakage from fuel injector Fuel injector clogging Inadequate fuel pressure Open or short circuit in fuel pump and related wiring harness Fuel pump mechanical malfunction Fuel line clogged Pressure regulator malfunction (built-in fuel pump unit) Fuel leakage from fuel system PCV valve malfunction A/C system operation is improper. Purge solenoid valve malfunction Air leakage from intake air system when engine runs high speed Improper operation variable valve timing control system Low engine compression Improper valve timing WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.6 CRANKS NORMALLY BUT WILL NOT START [MZI 3.7 V6]

6CRANKS NORMALLY BUT WILL NOT START
DESCRIPTIONThe starter cranks engine at normal speed but the engine will not run. Refer to the symptom troubleshooting " NO.5 ENGINE STALLS-AFTER START/AT IDLE " if this symptom appears after the engine stall. Fuel is in the tank. Battery is in normal condition.
POSSIBLE CAUSEVacuum leakage Poor fuel quality Air leakage from intake-air system Restriction in intake-air system Disconnected electrical connector External engine shut-off accessory Restriction in exhaust system Throttle valve restriction No battery power supply to PCM Open PCM ground or vehicle body ground PCM DTC is stored. Erratic signal to PCM APP sensor or related circuit malfunction TP sensor or related circuit malfunction Improper operation of drive-by-wire control system No signal from CKP sensor due to sensor, related wire or incorrect installation No signal from CMP sensor due to sensor, related wire or incorrect installation Ignition coil or related circuit malfunction Fuel leakage from injector Fuel injector is clogged. Inadequate fuel pressure Open or short circuit in fuel pump body and related wiring harness Fuel pump mechanical malfunction Fuel line clogged Pressure regulator malfunction (built-in fuel pump unit) Fuel leakage from fuel system PCV valve malfunction Purge solenoid valve malfunction Air leakage in intake air system when engine runs high speed Low engine compression Improper variable valve timing control system operation Improper valve timing WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.7 SLOW RETURN TO IDLE [MZI 3.7 V6]

7SLOW RETURN TO IDLE
DESCRIPTIONEngine takes more time than normal to return to idle speed.
POSSIBLE CAUSEPCM DTC is stored. Air leakage from intake-air system Throttle body malfunction Erratic signal from PSP switch Thermostat is stuck open. CHT sensor malfunction

NO.8 ENGINE RUNS ROUGH/ROLLING IDLE [MZI 3.7 V6]

8ENGINE RUNS ROUGH/ROLLING IDLE
DESCRIPTIONEngine speed fluctuates between specified idle speed and lower speed and engine shakes excessively. Idle speed is too slow and engine shakes excessively.
POSSIBLE CAUSEIdle learning of drive-by-wire control system is not completed. Poor fuel quality Air cleaner restriction Vacuum leakage Disconnected electrical connectors Air leakage from intake-air system parts No battery power supply to PCM Open or short circuit in PCM ground circuit PCM DTC is stored. Engine overheating MAF sensor or related circuit malfunction A/C system operation is improper. Power steering pressure switch or related circuit malfunction Erratic signal from CKP sensor Ignition system malfunction Ignition coil malfunction Ignition coil related circuit malfunction Spark plug malfunction Fuel leakage from fuel injector Fuel injector clogging Improper operation of drive-by-wire control system Inadequate fuel pressure Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) Fuel leakage from fuel system Purge solenoid valve malfunction PCV valve malfunction Erratic or no signal from CMP sensor Improper variable valve timing control system operation Low engine compression Improper valve timing WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.9 FAST IDLE/RUNS ON [MZI 3.7 V6]

9FAST IDLE/RUNS ON
DESCRIPTIONThe engine speed continues at fast idle after warm-up. The engine runs after the ignition is off.
POSSIBLE CAUSECHT sensor malfunction Improper load signal input Refrigerant pressure sensor malfunction Communication error between instrument cluster and PCM Erratic signal from climate control unit (A/C switch, fan switch malfunction) Evaporator temperature sensor malfunction Open or short circuit in wiring harness between climate control unit and instrument cluster Erratic signal from PSP switch TR switch malfunction Communication error between TCM and PCM Improper operation of drive-by-wire control system Air leakage from intake-air system Cruise control system operation improperly APP sensor malfunction

NO.10 LOW IDLE/STALLS DURING DECELERATION [MZI 3.7 V6]

10LOW IDLE/STALLS DURING DECELERATION
DESCRIPTIONEngine stops unexpectedly at the beginning of deceleration or recovery from deceleration.
POSSIBLE CAUSEImproper A/C magnetic clutch operation Vacuum leakage Air leakage from intake-air system Improper routing vacuum line PCM DTC is stored. Improper operation of drive-by-wire control system EVAP control system malfunction Erratic signal to PCM APP sensor or related circuit malfunction TP sensor or related circuit malfunction MAF sensor or related circuit malfunction Brake switch or related circuit malfunction TR switch or related circuit malfunction VSS or related circuit malfunction

NO.11 ENGINE STALLS/QUITS, ENGINE RUNS ROUGH, MISSES, BUCK/JERK, HESITATION/STUMBLE, SURGES [MZI 3.7 V6]

11ENGINE STALLS/QUITS-ACCELERATION/CRUISE ENGINE RUNS ROUGH-ACCELERATION/CRUISE MISSES-ACCELERATION/CRUISE BUCK/JERK-ACCELERATION/CRUISE/DECELERATION HESITATION/STUMBLE-ACCELERATION SURGES-ACCELERATION/CRUISE
DESCRIPTIONEngine stops unexpectedly at the beginning of acceleration or during acceleration. Engine stops unexpectedly while cruising. Engine speed fluctuates during acceleration or cruising. Engine misses during acceleration or cruising. Vehicle bucks/jerks during acceleration, cruising, or deceleration. Momentary pause at beginning of acceleration or during acceleration. Momentary minor irregularity in engine output.
POSSIBLE CAUSEVacuum leakage Air cleaner restriction Air leakage from intake-air system parts Intake air system restriction Poor fuel quality Disconnected electrical system connector Loose attaching bolts or worn engine mounts PCM DTC is stored. Engine overheating Throttle body restriction or clogged Erratic signal to PCM APP sensor or related circuit malfunction TP sensor or related circuit malfunction CKP sensor or related circuit malfunction MAF sensor or related circuit malfunction TP sensor or related circuit malfunction Battery or related circuit malfunction VSS or related circuit malfunction Erratic signal from CKP sensor Fuel leakage from fuel injector Fuel injector clogging Improper operation of drive-by-wire control system Restriction in exhaust system Inadequate fuel pressure Intermittent open or short circuit in fuel pump circuit Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) Fuel leakage from fuel system Improper A/C system operation Improper operation of cruise control system Improper air/fuel mixture ratio control operation A/F sensor or related circuit malfunction PCV valve malfunction Check valve (two-way) malfunction integrated with fuel tank Purge solenoid valve malfunction Fuel flow into evaporative purge hose Erratic signal or no signal from CMP sensor Low engine compression Improper valve timing due to jumping out timing chain ATX malfunction WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.12 LACK/LOSS OF POWER-ACCELERATION/CRUISE [MZI 3.7 V6]

12LACK/LOSS OF POWER-ACCELERATION/CRUISE
DESCRIPTIONPerformance is poor under load (such as power down when climbing hills).
POSSIBLE CAUSEVacuum leakage Restriction in intake-air system Air leakage from intake-air system parts Poor fuel quality PCM DTC is stored. Engine overheating Intake air temperature too hot Erratic signal to PCM APP sensor or related circuit malfunction MAF sensor or related circuit malfunction TP sensor or related circuit malfunction IAT sensor or related circuit malfunction CKP sensor or related circuit malfunction VSS or related circuit malfunction Erratic signal from CKP sensor Fuel leakage from fuel injector Fuel injector clogging Throttle body restriction or clogged Improper operation of drive-by-wire control system Restriction in exhaust system Inadequate fuel pressure Open or short in fuel pump related circuit Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) Improper A/C system operation Improper A/C cut-off operation PCV valve malfunction Purge control solenoid malfunction Erratic signal or no signal from CMP sensor Improper variable valve timing control operation Low engine compression Improper valve timing due to jumping out of timing chain ATX malfunction Brake dragging WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.13 KNOCKING/PINGING-ACCELERATION/CRUISE [MZI 3.7 V6]

13KNOCKING/PINGING-ACCELERATION/CRUISE
DESCRIPTIONSound is heard when air/fuel mixture is ignited by something other than spark plug (such as hot spot in combustion chamber).
POSSIBLE CAUSEEngine overheating due to cooling system malfunction IAT sensor malfunction MAF sensor malfunction PCM DTC is stored. Inadequate engine compression Erratic signal from CMP sensor Erratic signal from CKP sensor Inadequate fuel pressure Intermittent open or short circuit in fuel pump circuit Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) KS malfunction Improper ignition timing Poor fuel quality (i.e. Fuel RON is not specified, excessive cleaning agents added in fuel.) WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.14 POOR FUEL ECONOMY [MZI 3.7 V6]

14POOR FUEL ECONOMY
DESCRIPTIONFuel economy is unsatisfactory.
POSSIBLE CAUSEContaminated air cleaner element Improper ATF level Poor fuel quality Improper coolant level Brake dragging Improper tire pressure PCM DTC is stored. Engine cooling system malfunction Weak spark Ignition system malfunction (ignition coil, ignition coil related circuit or spark plug malfunction) Inadequate fuel pressure Intermittent open or short circuit in fuel pump circuit Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) Improper variable valve timing control system operation Exhaust system clogging Contaminated MAF sensor Improper engine compression PCV valve malfunction Improper valve timing due to jumping out of timing chain WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.15 EMISSION COMPLIANCE [MZI 3.7 V6]

15EMISSION COMPLIANCE
DESCRIPTIONFails emissions test.
POSSIBLE CAUSEVacuum lines leakage or blockage Disconnected electrical system connector Maintenance schedule is not followed. Leakage from intake manifold Air cleaner element clogging or restriction Throttle body restrict or clogged PCM DTC is stored. Cooling system malfunction Fuel-filler cap malfunction Ignition system malfunction Ignition coil malfunction Ignition coil related circuit malfunction Spark plug malfunction Inadequate fuel pressure Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) Improper air/fuel mixture ratio control operation Bend or open circuit A/F sensor wiring harness Exhaust system clogging PCV valve malfunction or incorrect valve installation Improper engine compression Fuel tank ventilation system malfunction Charcoal canister damage Catalyst converter malfunction Engine internal parts malfunction Excessive carbon is built up in combustion chamber. Improper valve timing WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.16 HIGH OIL CONSUMPTION/LEAKAGE [MZI 3.7 V6]

16HIGH OIL CONSUMPTION/LEAKAGE
DESCRIPTIONOil consumption is excessive.
POSSIBLE CAUSEPCV valve malfunction Improper dipstick Improper engine oil viscosity Engine internal parts malfunction

NO.17 COOLING SYSTEM CONCERNS-OVERHEATING [MZI 3.7 V6]

17COOLING SYSTEM CONCERNS-OVERHEATING
DESCRIPTIONEngine runs at higher than normal temperature/overheats.
POSSIBLE CAUSEImproper coolant level Coolant leakage Improper water/anti-freeze mixture Poor radiator condition Radiator hoses damage Improper or damaged radiator cap Coolant overflow system malfunction Fans reverse rotation Blown cooling fan control related fuses PCM DTC is stored. A/C system operation is improper. Cooling fan is inoperative. Improper tension of drive belt Drive belt damage Coolant leakage from climate control unit Improper water temperature gauge operation CHT sensor malfunction Instrument cluster malfunction Thermostat malfunction Cylinder block or cylinder head malfunction (cracked, coolant restriction)

NO.18 COOLING SYSTEM CONCERNS-RUNS COLD [MZI 3.7 V6]

18COOLING SYSTEM CONCERNS-RUNS COLD
DESCRIPTIONEngine takes excessive time to reach normal operating temperature.
POSSIBLE CAUSEA/C and heater system malfunction Thermostat malfunction Cooling fan system malfunction Improper water temperature gauge operation CHT sensor malfunction Instrument cluster malfunction

NO.19 EXHAUST SMOKE [MZI 3.7 V6]

19EXHAUST SMOKE
DESCRIPTIONBlue, black, or white smoke from exhaust system.
POSSIBLE CAUSEBlue smoke (Burning oil): PCV valve malfunction Engine internal oil leakage White smoke (Water in combustion): Cooling system malfunction (coolant loss) Engine internal coolant leakage Black smoke (Rich fuel mixture): Air cleaner restriction Intake-air system is collapsed or restricted. PCM DTC is stored. Erratic signal to PCM APP sensor or related circuit malfunction CHT sensor or related circuit malfunction IAT sensor or related circuit malfunction MAF sensor or related circuit malfunction MAP sensor or related circuit malfunction A/F sensor or related circuit malfunction HO2S or related circuit malfunction TP sensor or related circuit malfunction VSS or related circuit malfunction Excessive fuel pressure Fuel pump mechanical malfunction Fuel line restriction or clogging Pressure regulator malfunction (built-in fuel pump unit) Ignition system malfunction Ignition coil malfunction Ignition coil related circuit malfunction Spark plug malfunction Erratic CMP sensor signal Improper engine compression Improper fuel injection timing and amount WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.20 FUEL ODOR (IN ENGINE COMPARTMENT) [MZI 3.7 V6]

20FUEL ODOR (IN ENGINE COMPARTMENT)
DESCRIPTIONGasoline fuel smell or visible leakage.
POSSIBLE CAUSEFuel leakage from fuel system Excessive fuel line pressure Pressure regulator malfunction (built-in fuel pump unit) Fuel tank vent system blockage Purge solenoid valve malfunction PCM DTC is stored. Charcoal canister malfunction WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.23 A/C DOES NOT WORK SUFFICIENTLY [MZI 3.7 V6]

23A/C DOES NOT WORK SUFFICIENTLY
DESCRIPTIONA/C compressor magnetic clutch does not engage when the A/C switch is turned on.
POSSIBLE CAUSEPCM, climate control unit or instrument cluster DTC is stored. Refrigerant pressure sensor malfunction Improper refrigerant charging amount Seized magnetic clutch Evaporator temperature sensor malfunction Open or short circuit in wiring harness between evaporator temperature sensor and climate control unit Instrument cluster malfunction (Does not receive A/C request signal from climate control unit or transmit it to PCM.) Information display malfunction Climate control unit malfunction (A/C switch malfunction or climate control unit does not determine A/C request or transmit the A/C request signal.) Open or short circuit in wiring harness between climate control unit terminal 1L and instrument cluster terminal 1A (Manual air conditioner) Magnetic clutch malfunction Open circuit in wiring harness between magnetic clutch terminal A and body ground A/C relay malfunction Open or short circuit in wiring harness between A/C relay and PCM terminal 1W Open in wiring harness between ignition switch (IG2) () /IG2 relay () and A/C relay Open circuit in wiring harness between battery positive terminal and A/C relay Open circuit in wiring harness between A/C relay and magnetic clutch

NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [MZI 3.7 V6]

24A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY
DESCRIPTIONA/C compressor magnetic clutch does not disengage.
POSSIBLE CAUSEA/C compressor magnetic clutch engagement is stuck. A/C relay is stuck closed. Short to ground in wiring harness between A/C relay and PCM Short to power supply in A/C relay to magnetic clutch Climate control module malfunction (A/C switch signal stuck on.) Communication error between PCM and climate control module

NO.25 A/C DOES NOT CUT OFF UNDER WIDE OPEN THROTTLE CONDITIONS [MZI 3.7 V6]

25A/C DOES NOT CUT OFF UNDER WOT CONDITIONS
DESCRIPTIONA/C compressor magnetic clutch does not disengage under WOT.
POSSIBLE CAUSEAPP sensor malfunction Loosely installed accelerator pedal

NO.26 EXHAUST SULPHUR SMELL [MZI 3.7 V6]

26EXHAUST SULPHUR SMELL
DESCRIPTIONRotten egg smell (sulphur) from exhaust.
POSSIBLE CAUSEElectrical connectors are disconnected or connected poorly. Charcoal canister malfunction Vacuum lines are disconnected or connected improperly. Improper fuel pressure Poor fuel quality WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.28 FUEL FILLING SHUT OFF CONCERNS [MZI 3.7 V6]

28FUEL FILLING SHUT OFF CONCERNS
DESCRIPTIONFuel does not shut off properly.
POSSIBLE CAUSEClogged EVAP pipes Nonreturn valve malfunction Fuel shut-off valve malfunction Fuel nozzle malfunction Fuel nozzle is not inserted correctly. WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

NO.29 SPARK PLUG CONDITION [MZI 3.7 V6]

29SPARK PLUG CONDITION
DESCRIPTIONIncorrect spark plug condition.
POSSIBLE CAUSENOTE: Inspecting spark plugs condition can determine whether problem is related to a specific cylinder or possibly all cylinders. Wet/carbon stuck on specific plug: Spark-Weak, not visible Air/fuel mixture-Excessive fuel injection volume Compression-No compression, low compression Malfunction spark plug Grayish white with specific plug: Air/fuel mixture-Insufficient fuel injection volume Malfunction spark plug Wet/carbon is stuck on all plugs: Spark-Spark rich, excessive fuel line pressure Air/fuel mixture-Too rich Erratic signal to PCM CHT sensor or related circuit malfunction MAF sensor or related circuit malfunction A/F sensor or related circuit malfunction HO2S or related circuit malfunction Compression-Low compression Clogging in intake/exhaust system Poor fuel quality Grayish white with all plugs: Air/fuel mixture-Too lean, insufficient fuel line pressure Erratic signal to PCM CHT sensor or related circuit malfunction MAF sensor or related circuit malfunction A/F sensor or related circuit malfunction HO2S or related circuit malfunction WARNING: The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .) CAUTION: Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.
NOTE
Inspecting spark plugs condition can determine whether problem is related to a specific cylinder or possibly all cylinders.
WARNING
The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before servicing the fuel system: Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel. Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete "BEFORE SERVICE PRECAUTION" and "AFTER SERVICE PRECAUTION" described in this manual. (See BEFORE SERVICE PRECAUTION [MZI 3.7 V6] .) (See AFTER SERVICE PRECAUTION [MZI 3.7 V6] .)
CAUTION
Disconnecting/connecting quick release connector without cleaning it may cause damage to fuel pipe and quick release connector. Always clean quick release connector joint area before disconnecting/connecting, and make sure that it is free of foreign material.

Water Sprinkling Method

  1. If malfunction occurs only under high humidity or rainy/snowy weather, perform the following steps
CAUTIONIndirectly change the temperature and humidity by spraying water onto the front of the radiator. If a vehicle is subject to water leakage, the leakage may damage the control module. When testing a vehicle with a water leakage problem, special caution must be used.

Scheme 124

Scheme 124
Scheme 124
  1. Connect the M-MDS to the DLC-2 if you are inspecting sensors or switches.
  2. Switch the ignition to ON (Engine off). NOTE: If the engine starts and runs, perform the following steps at idle.
  3. Access PIDs for sensor or switch if you are inspecting sensors or switches.
  4. If you are inspecting the switch, turn it on manually.
  5. Spray water onto the vehicle or run it through a car wash. If PID value is unstable or malfunction occurs, repair or replace part if necessary.

Finding irregular signals

  1. While referring to «ON-BOARD DIAGNOSTIC TEST [MZI 3.7 V6]»(ref-581634-S14823860442013101400000) , use the PID/DATA monitor and record function to inspect the input signal system relating to the problem.
  1. Start the engine and idle the vehicle. You can assume that any signals that are out of specification by a wide margin are irregular.
  2. When recreating the problem, any sudden change in monitor input signals that is not intentionally created by the driver can be determined as irregular.

Locating the source of unusual signals

CAUTIONCompare the M-MDS monitor voltage with the measurement voltage using the digital measurement system function. If you use another tester, misreading may occur. When measuring voltage, attach the tester GND to the GND of the PCM that is being tested, or to the engine itself. If this is not performed, the measured voltage and actual voltage may differ. After connecting the pin to a waterproof coupler, confirming continuity and measuring the voltage, inspect the waterproof connector for cracks. If there are any, use sealant to fix them. Failure to do this may result in deterioration of the wiring harness or terminal from water damage, leading to problems with the vehicle.

Scheme 125

Scheme 125: Variable resistance type (TP sensor)
Scheme 125: Variable resistance type (TP sensor)

If active command mode function of the M-MDS is used

  1. Start the engine.
  2. Disconnect the vacuum hose between the purge solenoid valve and the charcoal canister.
  3. Put the finger to the purge solenoid valve and verify that there is no vacuum applied when the engine is cold. If there is a vacuum, inspect the following: Wiring harness and connectors (Purge solenoid valve terminal B-PCM terminal 2H) Purge solenoid vale (stuck open) (See «PURGE SOLENOID VALVE INSPECTION [MZI 3.7 V6]»(ref-581680-S23250791582013101400000) .)
  4. Connect the M-MDS to the DLC-2 and verify that the DTC P0443:00 is shown. If the P0443:00 are displayed, perform the DTC inspection. (See «DTC P0443:00 [MZI 3.7 V6]»(ref-581634-S23360867552013101400000) .)
  5. Select the PCM PID EVAPCP.
  6. Increase the duty value of the purge solenoid valve to 50 % and inspect if the operation sound of the valve is heard. If the operation sound is heard, inspect for the loose or damaged vacuum hose. (Intake manifold-Purge solenoid valve-Charcoal canister) If the operation sound is not heard, perform the purge solenoid valve inspection. (See «PURGE SOLENOID VALVE INSPECTION [MZI 3.7 V6]»(ref-581680-S23250791582013101400000) .)
  7. Warm up the engine to normal operating temperature.
  8. Monitor the EVAPCP PID using the M-MDS, and drive the vehicle approx. 2,000 rpm for 30 s or more . If the EVAPCP PID is 0 % , inspect the PCM PIDs MAF, APP1, APP2, TP REL and LOAD.

f active command mode function of the M-MDS is not used

  1. Start the engine.
  2. Disconnect the vacuum hose between the purge solenoid valve and the charcoal canister.
  3. Put the finger to the purge solenoid valve and verify that there is no vacuum applied when the engine is cold. If there is a vacuum, inspect the following: Wiring harness and connectors (Purge solenoid valve-PCM terminal 2H) Purge solenoid vale (stuck open) (See «PURGE SOLENOID VALVE INSPECTION [MZI 3.7 V6]»(ref-581680-S23250791582013101400000) .)
  4. Connect the M-MDS to the DLC-2 and verify that the DTC P0443:00 is shown. If the P0443:00 are displayed, perform the DTC inspection. (See «DTC P0443:00 [MZI 3.7 V6]»(ref-581634-S23360867552013101400000) .)
  5. Access the PCM PIDs EVAPCP and ECT.
  6. Verify that the ECT PID is more than 78 °C {172 °F} . If the ECT PID reading indicates less than 78 °C {172 °F} , perform the CHT sensor inspection. (See «CYLINDER HEAD TEMPERATURE (CHT) SENSOR INSPECTION [MZI 3.7 V6]»(ref-581669-S31089791712013101400000) .)
  7. Set the vehicle on the dynamometer or chassis roller. WARNING: When the dynamometer or chassis roller is operating, there is a possibility that the operator may come into contact with or be caught up in the rotating parts, leading to serious injuries or death. When performing work while the dynamometer or chassis roller is operating, be careful not to come into contact with or caught up in any of the rotating parts.
  8. Drive the vehicle approx. 2,000 rpm for 30 s or more . If there is no vacuum, inspect the following: Wiring harness and connector (Main relay-Purge solenoid valve-PCM terminal 2H) Purge solenoid valve (See «PURGE SOLENOID VALVE INSPECTION [MZI 3.7 V6]»(ref-581680-S23250791582013101400000) .) MAF, APP1, APP2, TP REL and LOAD PIDs If there is vacuum, inspect the following: Vacuum hose (Purge solenoid valve-Charcoal canister)

Cooling fans do not operate

  1. Inspect for followings: Open circuit between fan control module relay and battery positive terminal Open circuit between fan control module relay and PCM terminal 1BI Open circuit between fan control module relay and fan control module terminal 1C Open circuit between fan control module terminal 1A and ground Poor connection of the fan control module connector Fan control module relay malfunction (See «RELAY INSPECTION»(ref-581640-S26749992412013101400000) .) Open or short circuit between fan control module terminal 1B and PCM terminal 1AY Open or short circuit between ignition switch (IG1) *1 /IG1 relay *2 and fan control module relay If there is malfunction, repair or replace malfunctioning part. If there is no malfunction, replace the fan control module. (See «COOLING FAN MOTOR REMOVAL/INSTALLATION [MZI 3.7 V6]»(ref-581683-S04818170622013101400000) .)

*1 Vehicles without advanced keyless entry and push button start system

*2 Vehicles with advanced keyless entry and push button start system

Cooling fan motor No.1 does not operate

  1. Inspect for followings: Open or short to ground circuit between fan control module and cooling fan motor No.1 Poor connection of the fan control module connector or cooling fan motor No.1 connector Cooling fan motor No.1 malfunction (See «COOLING FAN MOTOR INSPECTION [MZI 3.7 V6]»(ref-581683-S25397741782013101400000) .) If there is malfunction, repair or replace malfunctioning part. If there is no malfunction, replace the fan control module. (See «COOLING FAN MOTOR REMOVAL/INSTALLATION [MZI 3.7 V6]»(ref-581683-S04818170622013101400000) .)

Cooling fan motor No.2 does not operate

  1. Inspect for followings: Open or short to ground circuit between fan control module and the cooling fan motor No.2 Poor connection of the fan control module connector or the cooling fan motor No.2 connector Cooling fan motor No.2 malfunction (See «COOLING FAN MOTOR INSPECTION [MZI 3.7 V6]»(ref-581683-S25397741782013101400000) .) If there is malfunction, repair or replace malfunctioning part. If there is no malfunction, replace the fan control module. (See «COOLING FAN MOTOR REMOVAL/INSTALLATION [MZI 3.7 V6]»(ref-581683-S04818170622013101400000) .)

For Right Bank

  1. Disconnect OCV (RH) connector.
  2. Warm up the engine and it at idle.
  3. Apply the battery voltage to the OCV and verify that the engine idles roughly or stalls. If the engine idles roughly or stalls, inspect the timing belt component (valve timing deviation). If the engine does not idle roughly or stall, go to the next step.
  4. Remove the OCV (RH) and perform the spool valve operation inspection. (See «OIL CONTROL VALVE (OCV) REMOVAL/INSTALLATION [MZI 3.7 V6]»(ref-581682-S35459348242013101400000) .) If not as specified, inspect the following: OCV (RH) (See «OIL CONTROL VALVE (OCV) INSPECTION [MZI 3.7 V6]»(ref-581682-S19743142042013101400000) .) Harnesses and connectors between OCV (RH) and PCM have an open or short circuit. If as specified, inspect the following right bank hydraulic passages for clogging or leakage, or both. Oil pressure switch-OCV OCV-Camshaft Camshaft internal passage
  5. If they are normal, replace the right bank camshaft pulley (with built-in variable valve timing actuator).

When idling can be continued

For Left Bank

  1. Disconnect OCV (LH) connector.
  2. Warm up the engine to idle.
  3. Apply the battery voltage to the OCV and verify that the engine idles roughly or stalls. If the engine idles roughly or stalls, inspect the timing belt component (valve timing deviation). If the engine does not idle roughly or stall, go to the next step.
  4. Remove the OCV (LH) and perform spool valve operation inspection. (See «OIL CONTROL VALVE (OCV) REMOVAL/INSTALLATION [MZI 3.7 V6]»(ref-581682-S35459348242013101400000) .) If not as specified, inspect the following: OCV (LH) (See «OIL CONTROL VALVE (OCV) INSPECTION [MZI 3.7 V6]»(ref-581682-S19743142042013101400000) .) Harnesses and connectors between OCV (LH) and PCM have an open or short circuit. If as specified, inspect the following left bank hydraulic passages for clogging or leakage or both. Oil pressure switch- OCV OCV-Camshaft Camshaft internal passage
  5. If they are normal, replace the left bank camshaft pulley (with built-in variable valve timing actuator).

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