SFI SYSTEM (w/ Dual VVT-i), Diagnostic DTC:P1603, P1605

DTC Code DTC Name
P1603 Engine Stall History
P1605 Rough Idling

DESCRIPTION

P1603

After starting the engine, this DTC is stored when the engine stops without the ignition switch being operated.

Using the GTS, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

It is necessary to check if the vehicle has run out of fuel before performing troubleshooting, as this DTC is also stored when the engine stalls due to running out of fuel.

P1605 [MT]

This DTC is stored if the engine speed drops below the set speed.

Using the GTS, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

It is necessary to check if the vehicle ran out of fuel before performing troubleshooting, as this DTC is also stored when idling is unstable due to running out of fuel.

P1605 [AT]

This DTC is stored if the combustion state of any cylinder is unstable.

Using the GTS, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

It is necessary to check if the vehicle ran out of fuel before performing troubleshooting, as this DTC is also stored when idling is unstable due to running out of fuel.

DTC No. DTC Detection Condition
P1603

After monitoring for startability problems (P1604) finishes and 5 seconds or more have elapsed after starting the engine, with the engine running, the engine stops (the engine speed drops to 200 rpm or less) without the ignition switch being operated for 0.5 seconds or more.

(1 trip detection logic)
P1605 [MT]

After 5 seconds or more have elapsed after starting the engine, with the engine running, the engine speed drops to 400 rpm or less

(1 trip detection logic)
P1605 [AT]

When idling with the accelerator pedal released and the vehicle stopped, this item detects when the combustion is unstable from the sudden changes in engine speed between the cylinders.

Detection for 2 to 10 seconds according to the combustion state.

(1 trip detection logic)
Trouble Area
Ignition system

  • Spark plug

  • Ignition coil assembly
Fuel system

  • Fuel injector assembly

  • Fuel pump

  • Fuel pump control circuit

  • Fuel line

  • Purge VSV system

  • Fuel quality (existence of foreign matter, degradation)
Intake and exhaust systems

  • Mass air flow meter sub-assembly

  • Intake system (Air leaks or deposit accumulation)

  • Throttle body assembly

  • Air fuel ratio sensor

  • Heated oxygen sensor

  • Camshaft timing oil control assembly

  • Variable Valve Timing system (VVT system)

  • Brake booster assembly
Other control systems

  • ECM

  • Wire harness or connector

  • Knock control sensor

  • Engine coolant temperature sensor
Engine

  • Thermostat

  • Engine assembly

  • Engine mount
High load from another system

  • Air conditioning system

  • Power steering system

  • Electrical load signal system

  • A/T system

INSPECTION PROCEDURE

Tech Tips


  • In contrast to conventional DTCs for components, circuits and systems, DTCs P1603 and P1605 are used to estimate the malfunctioning area from problem symptoms and freeze frame data in response to symptoms such as "rough idling", "strong engine vibrations", etc. Such problem symptoms can occur even in the following conditions:


    • Driving with long-stored fuel (fuel that has remained in the tank for long periods of time)

    • Using fuel not acclimated to the climate during a change of seasons

    • Temporarily using low-quality fuel (fuel that contains water or has poor fuel properties)

  • DTCs related to engine stall and starting problems may be detected due to operations performed by the user. The following are a few examples. Ask questions to the user about how the vehicle is operated and give advice as necessary.


    • Ran out of fuel

    • Rolled down on a slope and engine stalls (backed up in D, moved forward in R)

  • In contrast to normal malfunction diagnosis for components, circuits and systems, DTCs P1603 and P1605 are used to determine the malfunctioning area from the problem symptoms and freeze frame data when the user mentions problems such as engine stall.

    As these DTCs can be stored as a result of certain user actions, even if these DTCs are output, if the customer makes no mention of problems, clear these DTCs without performing any troubleshooting and return the vehicle to the customer.

  • If any other DTCs are output, perform troubleshooting for those DTCs first.

  • Use any information from the customer problem analysis about the condition of the vehicle at the time when the problem occurred (how the engine stopped, conditions when the engine was restarted, etc.) as a reference.

    Symptom Suspected Area
    Engine vibration occurs and engine stops

    • Abnormal mass air flow meter sub-assembly output due to existence of foreign matter

    • Abnormal air fuel ratio due to malfunction of air fuel ratio sensor or heated oxygen sensor, air leaks in intake system or insufficient fuel supply
    Engine stops with no engine vibration Ignition system, injection stoppage, high load from external parts
    Engine can be started with accelerator pedal depressed Insufficient air volume
    Engine stalls or is difficult to start immediately after engine stalled, regardless of whether engine is cold or warm Deposits in intake system or combustion chamber caught temporarily on intake or exhaust valve

  • Read freeze frame data using the GTS. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

  • When confirming the freeze frame data, be sure to check all 5 sets of freeze frame data Click here.

  • When DTC P1603 (Engine Stall History) is stored, DTC P1605 (Rough Idling) is also stored. When confirming freeze frame data, check DTC P1605. The ECM stores DTC P1605 first. Therefore, 5 sets of freeze frame data can be confirmed through DTC P1605, enabling the technician to obtain more information.

  • When confirming freeze frame data, if there are multiple items related to the cause of the malfunction, perform troubleshooting for all related items.

  • Try to operate the vehicle under the conditions recorded in the freeze frame data which were present when the malfunction occurred. Confirm the data at this time and the data when the engine is idling (engine warmed up, no load, and shift lever in D or N) and compare this data with the freeze frame data.

  • Inspections take into account the fact that the malfunction may not have recurred and place emphasis on checking the vehicle conditions present at the time when the malfunction occurred.

  • When performing inspections, jiggle the relevant wire harnesses and connectors in an attempt to reproduce malfunctions that do not always occur.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    5. Read the DTCs.

      Result
      Result Proceed to
      Only DTC P1605 is output [MT] A
      Only DTC P1603 and/or P1605 is output [AT] B
      DTCs other than P1603 and/or P1605 are output C

      Tech Tips


      • If any DTCs other than P1603 or P1605 are output, troubleshoot those DTCs first.

      • Using freeze frame data, confirm the conditions the moment the DTC was stored and after the DTC was stored. This information can be useful when troubleshooting.


    B

    READ FREEZE FRAME DATA Click here

    C

    GO TO DTC CHART Click here

    A

  2. READ FREEZE FRAME DATA (ISC LEARNING VALUE)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Using the GTS, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Click here.

      Result
      Freeze Frame Data Item for DTC P1605 Result Suspected Area Action Proceed to
      ISC Learning Value Less than 6.2 L/s - Go to the next step A
      6.2 L/s or higher Throttle valve assembly Go to Engine Stalls (from step 11 (REMOVE FOREIGN OBJECT (CLEAN THROTTLE BODY ASSEMBLY)) B

    B

    GO TO ENGINE STALL Click here

    A

  3. READ FREEZE FRAME DATA (AFS VOLTAGE, SHORT FT AND LONG FT)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Using the GTS, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Click here.

      Result
      Freeze Frame Data Item for DTC P1605 Suspected Area Action Proceed to
      AFS Voltage Short FT Long FT
      3.8 V or higher 15% or higher - Fuel pump Go to Engine Stalls (from step 20 (PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP / SPEED)) NEXT
      Less than 2.8 V, or 3.8 V or higher Less than -15%, or 15% or higher Less than -15%, or 15% or higher

      • Mass air flow meter subassembly

      • Air fuel ratio sensor

      • Fuel pump

      		 Go to Engine Stalls (from step 15 (READ VALUE USING GTS (MAF))*
      2.8 V to 3.8 V -15% to 15% -15% to 15% - Go to Engine Stalls

      Tech Tips

      *: If the value of AFS Voltage, Short FT or Long FT is as specified, malfunction of a component listed in the "Suspected Area" column of the table is suspected.


    NEXT

    GO TO ENGINE STALL Click here

  4. READ FREEZE FRAME DATA


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Using the GTS, confirm the vehicle conditions recorded in the freeze frame data which were present when the DTC was stored Click here.

      Result
      Freeze Frame Data Item for DTC P1605 Suspected Area Action Proceed to

      • Rough Idle #1 to #4

      • Plural Cylinders Rough Idle

      		 Rough Idle Status Compression Leakage Count

      "One of Rough Idle #1 to #4 is ON"

      and

      "Plural Cylinders Rough Idle is OFF"

      		 "Misfire" 0

      • Spark plug

      • Ignition coil assembly

      • Fuel injector assembly

      		 Go to Rough Idling (from step 8) A

      One of the following is displayed:


      • Continuous poor combustion

      • Intermittent poor combustion

      • Low frequency poor combustion

      		 0

      • Fuel injector assembly

      • Spark plug

      • Ignition coil assembly
      Plural Cylinders Rough Idle is ON

      One of the following is displayed:


      • Misfire

      • Continuous poor combustion

      • Intermittent poor combustion

      • Low frequency poor combustion

      		 0

      • Mass air flow meter subassembly

      • Fuel injector assembly

      • Fuel system

      • Air fuel ratio sensor

      		 Go to Rough Idling (from step 15) B

      "One of Rough Idle #1 to #4 is ON"

      or

      "Plural Cylinders Rough Idle is ON"

      One of the following is displayed:


      • Misfire

      • Continuous poor combustion

      • Intermittent poor combustion

      • Low frequency poor combustion

      		 1 or more Pressure loss from valve damage, deposits jamming the valve etc. Check compression and clean deposits in combustion chamber and intake system. C

    B

    DETERMINE CAUSE OF MALFUNCTION FOR MULTIPLE OR ALL CYLINDERS Click here

    C

    PERFORM ACTIVE TEST USING GTS Click here

    A

  5. DETERMINE CAUSE OF MALFUNCTION FOR INDIVIDUAL CYLINDER


    1. Perform troubleshooting from Rough Idling step 8 (PERFORM ACTIVE TEST USING GTS (CONTROL THE INJECTION VOLUME)) and onward Click here.


    NEXT

    GO TO ROUGH IDLING Click here

  6. DETERMINE CAUSE OF MALFUNCTION FOR MULTIPLE OR ALL CYLINDERS


    1. Perform troubleshooting from Rough Idling step 15 (READ VALUE USING GTS (MAF)) and onward Click here.


    NEXT

    GO TO ROUGH IDLING Click here

  7. PERFORM ACTIVE TEST USING GTS


    1. Warm up the engine.

    2. Turn the ignition switch off.

    3. Connect the GTS to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Check the Cylinder Compression / Compression / Engine Speed of Cyl #1 to #4, Av Engine Speed of All Cyl.

      Tech Tips

      To display the entire Data List, press the pull down menu button next to Primary. Then select Compression.

    7. While the engine is not running, press the RIGHT or LEFT button to change Check the Cylinder Compression to ON.

      Tech Tips

      After performing the above procedure, Check the Cylinder Compression will start. Fuel injection for all cylinders is prohibited and each cylinder engine speed measurement enters standby mode.

    8. Crank the engine for about 10 seconds.

    9. Monitor the engine speed (Engine Speed of Cyl and Av Engine Speed of All Cyl) displayed on the GTS.

      Tech Tips

      At first, the GTS displays extremely high cylinder engine speed values. After approximately 10 seconds of engine cranking, each cylinder engine speed measurement will change to the actual engine speed.

      Note


      • Do not crank the engine continuously for 20 seconds or more.

      • If it is necessary to crank the engine again after Check the Cylinder Compression has been changed to ON and the engine has been cranked once, press Exit to return to the Active Test menu screen. Then change Check the Cylinder Compression to ON and crank the engine.

      • Use a fully-charged battery.

    10. Stop cranking the engine, and then change "Check the Cylinder Compression" to OFF after the engine stops.

      Note


      • If the Active Test is changed to OFF while the engine is being cranked, the engine will start.

      • When performing the Active Test, DTC P1604 (Startability Malfunction) may be stored.

      • After performing the Active Test, make sure to check and clear DTCs.

    11. Read the value.

      Tech Tips


      • If the value of Data List item "Engine Speed of Cyl" of a cylinder is higher than other cylinders, the cylinder may be malfunctioning.

      • If the value of Data List item "Engine Speed of Cyl" is high for only one cylinder, compression loss is suspected.

      Result
      Result Proceed to

      There is no variation in "Engine Speed of Cyl"

      (All cylinders display approximately the same value for "Engine Speed of Cyl")

      		 A

      There is variation in "Engine Speed of Cyl"

      (Only one cylinder displays a value for "Engine Speed of Cyl" that differs considerably)

      		 B

    B

    CHECK CYLINDER COMPRESSION PRESSURE Click here

    A

    CLEAN OFF ANY DEPOSITS

  8. CHECK CYLINDER COMPRESSION PRESSURE


    1. Measure the cylinder compression pressure. If the compression pressure of a cylinder is low, inspect the engine assembly and repair or replace parts as necessary Click here.

      Tech Tips

      Perform "Inspection After Repair" after repairing or replacing the engine assembly Click here.


    NEXT

    END