Downloaded from www.Manualslib.com manuals search engine 1A-4 Engine General Information and Diagnosis:
Driving Cycle
A “Driving Cycle” consists of engine startup and engine
shutoff.
2 Driving Cycle Detection Logic
The malfunction detected in the first driving cycle is
stored in ECM memory (in t he form of pending DTC) but
the malfunction indicator lamp does not light at this time.
It lights up at the second detection of same malfunction
also in the next driving cycle.
Pending DTC
Pending DTC means a DTC detected and stored
temporarily at 1 driving cycle of the DTC which is
detected in the 2 driving cycle detection logic.
Freeze Frame Data
ECM stores the engine and driving conditions (in the
form of data as shown in the figure) at the moment of the
detection of a malfunction in its memory. This data is
called “Freeze frame data”.
Therefore, it is possible to know engine and driving
conditions (e.g., whether the engine was warm or not,
where the vehicle was running or stopped, where air/fuel
mixture was lean or rich) when a malfunction was
detected by checking the freeze frame data. Also, ECM
has a function to store each freeze frame data for three
different malfunctions in the order as each malfunction is detected. Utilizing this function,
it is possible to know the
order of malfunctions that ha ve been detected. Its use is
helpful when rechecking or diagnosing a trouble.
Priority of freeze frame data:
ECM has 4 frames where the freeze frame data can be stor ed. The first frame stores the freeze frame data of the
malfunction which was detected first. Howe ver, the freeze frame data stored in this frame is updated according to the
priority described. (If malfunction as described in the upper square “1” is detected while the freeze frame data in the
lower square “2” has been stored, the freeze frame data “2” will be updated by the freeze frame data “1”.)
In the 2nd through the 4th frames, the freeze frame data of each malfunction is stored in the order as each malfunction
is detected. These data are not updated.
Shown in the table are examples of how freeze frame data are stored when two or more malfunctions are detected.
[A]: 1st or 2nd in parentheses here represents which position in the order
the malfunction is detected.
[A]
I3RB0A110002-01
Priority Freeze frame data in frame 1
1 Freeze frame data at initial detection of malfuncti
on among misfire detected (P0300 – P0304), fuel
system too lean (P0171) and fuel system too rich (P0172)
2 Freeze frame data when a malfunctio n other than those in “1” is detected
Malfunction detected order Frame
Frame 1 Frame 2 Frame 3 Frame 4
Freeze frame data to be updated 1st freeze frame
data 2nd freeze frame
data 3rd freeze frame
data
No malfunction No freeze frame data
1 P0401 (EGR)
detected Data at P0401
detectionData at P0401
detection
——
2 P0171 (Fuel system)
detected Data at P0171
detectionData at P0401
detectionData at P0171
detection
—
3 P0300 (Misfire)
detected Data at P0171
detectionData at P0401
detectionData at P0171
detectionData at P0300
detection
4 P0301 (Misfire)
detected Data at P0171
detectionData at P0401
detectionData at P0171
detectionData at P0300
detection
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-9
Air Intake System DescriptionS7RS0B1101006
The main components of the air intake system are air cleaner (1), air cleaner outlet hose (2), electric throttle body (3)
(for the details, refer to “Description of Electric Throttle Body System”.), and intake manifold (4).
The air (by the amount corresponding to throttle valve (5) opening and engine speed) is filtered by the air cleaner,
distributed by the intake, and finally drawn into each combusti on chamber. Electric throttle body is not equipped with
IAC valve for idle speed control. Idle speed control is done by the throttle actuator (6) which opens/closes the throttle
valve. (For the details, refer to “Description of Electric Throttle Body System”).
Description of Electric Throttle Body SystemS7RS0B1101007
The Electric Throttle Body System consists of electric throttle body asse mbly, APP sensor assembly, ECM and throttle
actuator control relay.
Among them, assembly components are as follows.
• Electric throttle body assembly: throttle valve, throttle actuator, 2 throttle position sensors
• APP sensor assembly: Accelerator pe dal, 2 accelerator position sensors
Operation Description
ECM (5) detects opening (depressed extent of pedal) of the accelerator pedal based on signal voltage of the APP
sensor (1) and using that data and engi ne operation condition, it calculates the optimum throttle valve opening. On the
other hand, it detects the throttle valve opening based on the signal voltage of the throttle position sensor (3) included
in the throttle body (2) and compares it with above calculated optimum throttle valve opening. When there is a
difference between them, ECM controls the duty ratio (100% – 0%) according to this difference to drive the throttle
actuator (motor) (4) included in the throttle body. When th ere is no difference, ECM controls the duty ratio to about
15% to maintain the throttle valve opening . In this way, the throttle valve (17) is opened and closed to achieve the
optimum throttle valve opening.
In this system, as the thrott le position sensor and APP sensor have 2 sensors (main and sub) each, highly accurate
and highly reliable control and abnormality detection are assured. Also, when ECM detects an abnormality in the
system, it turns off the th rottle actuator control relay (8) to step controlling the throttle actuator.
When the throttle actuator control relay is turned off, the throttle valve is fixed at the specified opening below from its
completely closed position (default openin g) by the force of the return spring and open spring included in the throttle
body.
This throttle body is not equipped with IAC valve for idle speed control. Idle speed control is done by the throttle
actuator which opens/closes the throttle valve.
4 2
1
3
5
6
I5RW0A110006-02
Downloaded from www.Manualslib.com manuals search engine 1A-22 Engine General Information and Diagnosis:
Diagnostic Information and Procedures
Engine and Emission Control System CheckS7RS0B1104001
Refer to the following items for the details of each step.Step Action Yes No 1 ) Customer complaint analysis
1) Perform customer complaint analysis referring to “Customer Complaint Analysis”.
Was customer complaint analysis performed? Go to Step 2. Perform customer
complaint analysis.
2 ) DTC / Freeze frame data check, record and clearance
1) Check for DTC (including pending DTC) referring to “DTC / Freeze Frame Data Check, Record and
Clearance”.
Is there any DTC(s)? Print DTC and freeze
frame data or write them
down and clear them by
referring to “DTC
Clearance”, and go to
St ep 3 .Go to Step 4.
3 ) Visual inspection
1) Perform visual inspection referring to “Visual Inspection”.
Is there any faulty condition? Repair or replace
malfunction part, and go
to Step 11.
Go to Step 5.
4 ) Visual inspection
1) Perform visual inspection referring to “Visual Inspection”.
Is there any faulty condition? Repair or replace
malfunction part, and go
to Step 11.
Go to Step 8.
5 ) Trouble symptom confirmation
1) Confirm trouble symptom referring to “Trouble Symptom Confirmation”.
Is trouble symptom identified? Go to Step 6.
Go to Step 7.
6 ) Rechecking and record of DTC / Freeze frame data
1) Recheck for DTC and freeze frame data referring to “DTC Check”.
Is there any DTC(s)? Go to Step 9.
Go to Step 8.
7 ) Rechecking and record of DTC / Freeze frame data
1) Recheck for DTC and freeze frame data referring to “DTC Check”.
Is there any DTC(s)? Go to Step 9.
Go to Step 10.
8 ) Engine basic inspection and engine symptom
diagnosis
1) Check and repair according to “Engine Basic Inspection”
and “Engine Symptom Diagnosis”.
Are check and repair complete? Go to Step 11. Check and repair
malfunction part(s), and
go to Step 11.
9 ) Troubleshooting for DTC
1) Check and repair according to applicable DTC diag. flow.
Are check and repair complete? Go to Step 11. Check and repair
malfunction part(s), and
go to Step 11.
10 ) Intermittent problems check
1) Check for intermittent problems referring to “Intermittent Problems Check”.
Is there any faulty condition? Repair or replace
malfunction part(s), and
go to Step 11.
Go to Step 11.
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-25
Step 2: DTC / Freeze Frame Data Check, Record and
Clearance
First, check DTC (including pending DTC), referring to
“DTC Check”. If DTC is indicated, print it and freeze
frame data or write them down and then clear them by
referring to “DTC Clearance”. DTC indicates malfunction
that occurred in the system but does not indicate
whether it exists now or it occurred in the past and the
normal condition has been restored now. To check which
case applies, check the sy mptom in question according
to Step 5 and recheck DTC according to Step 6 and 7.
Attempt to diagnose a trouble based on DTC in this step
only or failure to clear the DTC in this step will lead to
incorrect diagnosis, trouble diagnosis of a normal circuit
or difficulty in troubleshooting.
Step 3 and 4: Visual Inspection
As a preliminary step, be sure to perform visual check of
the items that support proper function of the engine
referring to “Visual Inspection”.
Step 5: Trouble Symptom Confirmation
Based on information obtained in “Step 1: Customer
Complaint Analysis: ” and “Step 2: DTC / Freeze Frame
Data Check, Record and Clearance: ”, confirm trouble
symptoms. Also, reconfirm DTC according to “DTC
Confirmation Procedure” described in each DTC diag.
flow.
Step 6 and 7: Rechecking and Record of DTC /
Freeze Frame Data
Refer to “DTC Check” for checking procedure.
Step 8: Engine Basic Inspection and Engine
Symptom Diagnosis
Perform basic engine check according to “Engine Basic
Inspection” first. When the end of the flow has been
reached, check the parts of the system suspected as a
possible cause referring to “Engine Symptom Diagnosis”
and based on symptoms appearing on the vehicle
(symptoms obtained through steps of customer
complaint analysis, trouble symptom confirmation and/or
basic engine check) and repair or replace faulty parts, if
any.
Step 9: Troubleshooting for DTC (See each DTC
Diag. Flow)
Based on the DTC indicated in Step 6 or 7 and referring
to the applicable DTC diag. flow, locate the cause of the
trouble, namely in a sensor, switch, wire harness,
connector, actuator, ECM or other part and repair or
replace faulty parts. Step 10: Intermittent Problems Check
Check parts where an intermit
tent trouble is easy to
occur (e.g., wire harness, connector, etc.), referring to
“Intermittent and Poor Connec tion Inspection in Section
00” and related circuit of DTC recorded in Step 2.
Step 11: Final Confirmation Test
Confirm that the problem symptom has gone and the
engine is free from any abnormal conditions. If what has
been repaired is re lated to the DTC, clear the DTC once,
perform DTC confirmation procedure and confirm that no
DTC is indicated.
Malfunction Indicator Lamp (MIL) CheckS7RS0B1104002
1) Turn ON ignition switch (with engine at stop) and check that MIL (1) lights.
If MIL does not light up (or MIL dims) but engine can
be starting, go to “MIL Does Not Come ON with
Ignition Switch ON and Engine Stop (but Engine Can
Be Started)” for troubleshooting.
If MIL does not light with ignition switch ON and
engine does not start though it is cranked up, go to
“ECM Power and Ground Circuit Check”.
2) Start engine and check that MIL turns OFF. If MIL remains ON and no DTC is stored in ECM, go
to “Malfunction Indicator Lamp Remains ON after
Engine Starts” for troubleshooting.
1
I4RS0A110012-01