
CONTROL SYSTEM
F1–35
F1
HTR12
(HO2S heater (rear))ON/OFFIgnition switch ON: ON (HO2S
heater operated)
Idle: ON (HO2S heater operated)Inspect following PIDs: IAT, MAF,
ECT, RPM, ACSW.4D
IAC (IAC valve) %Ignition switch ON: 0%
Idle: Approx. 60% (ECT 90°C {194
°F} and E/L not operating) Inspect following PIDs: IAT, RPM,
MAP, ECT, MAF, TP, INGEAR, TR,
PSP, ACSW.
Inspect IAC valve.4G, 4J
IASV (Variable air duct
control solenoid valve)ON/OFFECT is above 70 °C {158 °F}, engine
speed is above 5,800 rpm, and TP
opening angle is above 50%: ON
Others: OFFInspect following PIDs: ECT, RPM,
TP.
Inspect VAD control solenoid valve.4C
IAT
(Intake air temperature)°C°FIAT 20 °C {68 °F}: 20 °C {68 °F}
IAT 30 °C {86 °F}: 30 °C {86 °F}
Inspect IAT sensor. 2E
VIAT 20 °C {68 °F}: 2.4—2.6 V
IAT 30 °C {86 °F}: 1.7—1.9 V
IMRC (Variable tumble
control solenoid valve)ON/OFFEngine speed is below approx.
3,500 rpm: ON
Others: OFFInspect following PIDs: TP, ECT,
RPM.
Inspect variable tumble control
solenoid valve.4T
IMTV*
7 (Variable
Intake-air control
solenoid valve)ON/OFFEngine speed is below approx.
4,350 rpm: ON
Others: OFFInspect following PIDs: RPM.
Inspect VIC control solenoid valve.4R
INGEAR*
8 (Load/no
load condition)ON/OFFCPP or CPP/PNP is ON: OFF
Others: ONPerform applicable DTC
troubleshooting.1R, 1W
IVS (CTP condition)IDLE/ OFF
IDLECTP: IDLE
Others: OFF IDLEPerform applicable DTC
troubleshooting.2A
KNOCKR (Knocking
retard)°Ignition switch ON: 0°
Idle: 0°Inspect knock sensor. 2P, 2S
LOAD (Engine load) %Ignition switch ON: 0%
Idle (after warm up): approx.19%Inspect MAF sensor.—
LONGFT1 (long term
fuel trim)%Idle (after warm up): approx. –14—
14%Perform applicable DTC
troubleshooting.
(See F1–54 DTC TABLE)—
MAF (Mass airflow)g/sIgnition switch ON: approx. 0 g/s
Idle (after warm up): approx. 1.5 g/s
Inspect MAF sensor. 1P
VIgnition switch ON: approx. 0.7 V
Idle (after warm up): approx. 1.3 V
MAP (Manifold
absolute pressure)kPa, inHgIgnition switch ON (at sea level):
approx 101 kPa {29.8 inHg}
Inspect MAP sensor. 1J
VIgnition switch ON (at sea level):
approx 4.1 V
MIL (Malfunction
indicator lamp)ON/OFFIgnition switch ON: ON
Idle: OFFPerform applicable DTC
troubleshooting.
(See F1–54 DTC TABLE)—
MIL_DIS (Trabelled
distance since the MIL
illuminated)km, mileNo DTC: 0 km {0 mile}
DTC detected: Not 0 km {0 mile}Perform applicable DTC
troubleshooting.
(See F1–54 DTC TABLE)—
O2S11 (Front oxygen
sensor)VIgnition switch ON: 0—1.0 V
Idle (After warm up): 0—1.0 V
Inspect HO2S (front). 1AB
Rich/LeanAcceleration (After warm up): Rich
Deceleration (After warm up): Lean
O2S12 (Rear oxygen
sensor)V Idle (After warm up): approx 0.6 V
Inspect HO2S (rear). 1Y
Rich/Lean Idle (After warm up): Rich
PSP (Power steering
pressure switch)Low/HighSteering wheel in straight ahead
position: Low
Others: HighInspect PSP switch. 1Z
RFCFLAG (Readness
function code)Learnt/Not
LearntBefore running PCM adaptive
memory procedure drive mode: Not
Learnt
After running PCM adaptive memory
procedure drive mode: LearntRun PCM adaptive memory
procedure drive mode.— Monitor item
(Definition)Unit/
ConditionCondition/Specification
(Reference)ActionPCM
terminal

F1–36
CONTROL SYSTEM
*1: Calculated value; differs from terminal voltage
*2: Refrigerant pressure switch (middle) turns on when the refrigerant pressure is 1.69—1.84 MPa {17.3—18.7
kgf/cm2, 247—265 psi}
*3: Refrigerant pressure switch (middle) turns off when the refrigerant pressure is 1.26—1.49 MPa {12.9—15.1
kgf/cm2, 184—214 psi}
*4: L3 and L8, LF (Intensely hot area) engine models
*5: Immobilizer system equipped model
*6: Immobilizer system not equipped
*7: L3 engine model only
*8: MTX model only
•Following PIDs are for the ATX models. If inspects for following PIDs, see K2–180 PID/DATA MONITOR
INSPECTION.
PIDs for the ATX models
—GEAR, LINEDES, LPS, OP_SW_B, SSA/SS1, SSB/SS2, SSC/SS3, TCS, TFT, TFTV, THOP, TR,
TR_SENS, TSS
RO2FT1 (Rear oxygen
sensor fuel trim)—Idle (after warm up): approx. –
0.03—0.03Perform applicable DTC
troubleshooting.—
RPM (Engine speed) rpm
LF Unleaded fuel (RON 90 or
above) model
No load: 600—700 rpm
E/L operating: 650—750 rpm
P/S operating: 650—750 rpm
A/C ON: 700—800 rpm
L3 4WD ATX model
No load: 650—750 rpm
E/L operating: 650—750 rpm
P/S operating: 650—750 rpm
A/C ON: 650—750 rpm*
2, 700—
800 rpm*3
Inspect CKP sensor. 2D, 2G
SEGRP (EGR valve
(stepping motor)
position)StepIgnition switch ON: 0 step
Idle: 0 step
Cranking: 0—60 stepsInspect following PIDs: MAF, TP,
ECT, RPM, VSS.
Inspect EGR valve.4E, 4H,
4K, 4N
SHRTFT1 (Short term
fuel trim)%Idle (after warm up): approx.–30—
25%Perform applicable DTC
troubleshooting.
(See F1–54 DTC TABLE)—
SPARKADV (Ignition
timing)°Ignition switch ON: BTDC 0°
Idle: BTDC approx. 10°Inspect following PIDs: MAF, TP,
ECT, RPM, INGEAR, TR, PSP,
ACSW, VPWR.
Inspect ignition timing.2J, 2M
TEST (Test mode) ON/OFF———
TP (TP)%CTP: 13—23%
WOT: 86—96%
Inspect TP sensor. 2A
VCTP: 0.65—1.15 V
WOT: 4.3—4.8 V
TPCT
(TP sensor voltage at
CTP )V0.65—1.15 V Inspect TP sensor. 2A
VPWR (Battery positive
voltage)V Ignition switch ON: B+Inspect main relay.
Inspect battery.2Y, 2Z
VSS (Vehicle speed) kph, mphVehicle speed 20 kph {12 mph}:
20 kph {12 mph}
Vehicle speed 40 kph {25 mph}:
20 kph {12 mph}Perform applicable DTC
troubleshooting.
(See F1–54 DTC TABLE)—
VT DUTY1*
7% Idle: 0%Inspect following PIDs: TP, ECT,
RPM.
Inspect OCV.2I, 2L Monitor item
(Definition)Unit/
ConditionCondition/Specification
(Reference)ActionPCM
terminal

F1–42
CONTROL SYSTEM
4B Cooling fan control Cooling fan relay IdlingECT below 100
°C {212 °F}B+•Inspect cooling fan
relay
•Inspect related
harness A/C operating Below 1.0
4CVAD control*
5VAD control
solenoid valveIgnition switch
ONEngine speed
below 5,800
rpmB+
•Inspect VAD control
solenoid valve
•Inspect related
harness Engine speed
above 5,800
rpmBelow 1.0
—*
7————
4DHO2S (Rear) heater
controlHO2S (Rear)
heaterIgnition switch
ONEngine speed
below 4,000
rpmB+
•Inspect HO2S (Front)
heater.
•Inspect related
harness Engine speed
above 4,000
rpmBelow 1.0
4EEGR valve #1 coil
controlEGR valve
(terminal E)Ignition switch ON Below 1.0•Inspect EGR valve
•Inspect related
harness Idle Below 1.0
4F Cooling fan control Cooling fan relay IdlingECT below 100
°C {212 °F}B+
•Inspect cooling fan
relay
•Inspect related
harness A/C operating
and refrigerant
pressure switch
(middle) ONBelow 1.0
4G IAC (+) IAC valve•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect IAC valve
•Inspect related
harness
4HEGR valve #2 coil
controlEGR valve
(terminal A)Ignition switch ON B+•Inspect EGR valve
•Inspect related
harness Idle B+
4I Starter relay controlStarter relay
(MTX)
TR switch (ATX)Under any condition Below 1.0•Perform “On-Board
Diagnostic Test”
•Inspect related
harness
4J IAC (–)IAC valve•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect IAC valve
•Inspect related
harness
4KEGR valve #3 coil
controlEGR valve
(terminal B)Ignition switch ON B+•Inspect EGR valve
•Inspect related
harness Idle B+
4L Cooling fan control Cooling fan relay IdlingECT below 100
°C {212 °F}B+•Inspect cooling fan
relay
•Inspect related
harness A/C operating Below 1.0
4MOCV control*
5OCV•Inspect using the wave profile.
(See F1–44 Inspection Using An
Oscilloscope (Reference).)•Inspect OCV valve
•Inspect related
harness
—*
7————
4NEGR valve #4 coil
controlEGR valve
(terminal F)Ignition switch ON Below 1.0•Inspect EGR valve
•Inspect related
harness Idle Below 1.0
4O A/C A/C relayA/C operating Below 1.0•Inspect A/C relay
•Inspect related
harness A/C not operating B+
4PFuel pump
control*
10Fuel pump relayIgnition switch ON B+•Inspect fuel pump
relay
•Inspect related
harness Cranking Below 1.0
Idle Below 1.0
—*
9———— Terminal Signal Connected to Test conditionVoltage
(V)Action

TROUBLESHOOTING
F1–59
F1
X: Applicable
Possible factor
Troubleshooting itemVariable valve timing system malfunction (L3 engine
model)
VICS malfunction
Engine overheating
Air cleaner element clogging or restriction
Air leakage from intake-air system (Loose tubes,
cracks, gaskets breakage)
IAC valve improper operation
Throttle body malfunction
VICS malfunction (L3 engine model)
VACS malfunction (L3 engine model)
Vacuum leakage (Vacuum hose damage, misrouting)
Ignition coil malfunction (e.g. open, short or cracks)
Initial ignition timing misadjustment (CKP sensor &
crankshaft pulley misadjustment)
Spark plug malfunction
High-tension leads malfunction (Cracks, open, low
resistance)
CKP sensor is damaged. (e.g. open or short circuits )
Crankshaft pulley is damaged
Improper gap between CKP sensor and crankshaft
Fuel pump malfunction (Mechanically or electrically)
Pressure regulator malfunction
Fuel hoses restriction or clogging
1 Melting of main or other fuses2 MIL illuminates x x x x x3 Will not crank4 Hard to start/long crank/erratic start/erratic
crankx x x x x x xxxxxx
5 Engine stalls. x x x x x xxxxxxxxxxx6 Cranks normally but will not start x x x x xxxxxxxxxxx7 Slow return to idle x8 Engine runs rough/rolling idle x x x x x x x x xxxxxxx9 Fast idle/runs on x x10 Low idle/stalls during deceleration x x xEngine stalls/quits. Acceleration/cruise x x x x x x x x xxxxxxxEngine runs rough. Acceleration/cruise x x x x x x x x xxxxxxxMissesAcceleration/cruise x x x x x x x x xxxxxxxBuck/jerk Acceleration/cruise/dece
lerationxxx x xx x x x xxxxxx
Hesitation/stumble Acceleration x x x x x x x x xxxxxxx
11
Surges Acceleration/cruise x x x x x x x x xxxxxxx
12 Lack/loss of powerAcceleration/cruise x x x x x x x x xxxxxxx13 Knocking/pingingAcceleration/cruise x x x14 Poor fuel economy x x x x x x x15 Emission compliance x x x x x x x x x16 High oil consumption/leakage17 Cooling system
concernsOverheating
18 Cooling system
concernsRuns cold
19 Exhaust smoke x x x x x x20 Fuel odor (in engine compartment)x21 Engine noise x x x22 Vibration concerns (engine)23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smell x x x x27 Constant voltage28 Spark plug condition x x x x x x29 ATX concernsUpshift/downshift
engagementSee Section K, TROUBLESHOOTING
A6E39802002

F1–60
TROUBLESHOOTING
X: Applicable
Possible factor
Troubleshooting item
Injectors malfunction (Leakage or clogging, inope-rative
Fuel leakage from fuel system (including insulator,
injector O-ring)
Fuel filters restriction or clogging
CMP sensor is damaged. (e.g. open or short circuit)
Camshaft is damaged.
Improper air/fuel mixture ratio control
Exhaust system restriction or clogging
Catalytic converter malfunction
EGR system malfunction (Unleaded gasoline models)
EVAP control system malfunction
PCV valve malfunction
Constant voltage supply circuit malfunction
Main relay malfunction (Mechanically or electrically)
ECT sensor malfunction
TR sensor misadjustment (ATX)
TR sensor malfunction (ATX)
Break switch and related circuit malfunction
Manifold absolute pressure sensor and related circuit
malfunction
HO2S and related circuit malfunction (Unleaded
gasoline models)
Variable resistor misadjustment (Leaded gasoline
models)
Improper electrically controlled 4WD system operation
1 Melting of main or other fuses2 MIL illuminates x x x x x x x3 Will not crankxx4 Hard to start/long crank/erratic start/erratic
crankx xx xxx x
5 Engine stalls. After start/at idle x x x x x x x x x6 Cranks normally but will not start x x x xxxxxx x7 Slow return to idlex8 Engine runs rough/rolling idle xxxxxx xxx x9 Fast idle/runs onx10 Low idle/stalls during deceleration x x x x xEngine stalls/quits.Acceleration/cruisex xxxxx xxxxx xEngine runs rough. Acceleration/cruisex xxxxx xxxxx xMissesAcceleration/cruisex xxxxx xxxxx xBuck/jerk Acceleration/cruise/
decelerationx xxxxx xxxxx x
Hesitation/stumble Acceleration xxxxxx xxxxx x
11
Surges Acceleration/cruise xxxxxx xxxxx x
12 Lack/loss of power Acceleration/cruise x x x x x x x x13 Knocking/pingingAcceleration/cruise x14 Poor fuel economy x x x x x x15 Emission compliancexxxxxxxxx x16 High oil consumption/leakage x17 Cooling system concerns Overheating18 Cooling system concernsRuns cold19 Exhaust smoke x x20 Fuel odor (in engine compartment) x x21 Engine noise22 Vibration concerns (engine)x23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smell x x27 Constant voltage x x x x x28 Spark plug condition x x x x29 ATX concernsUpshift/downshift/en
gagementSee Section K, TROUBLESHOOTING
A6E39802003

TROUBLESHOOTING
F1–61
F1
End Of Sie
X: Applicable
Possible factor
Troubleshooting itemIAT sensor and related circuit malfunction
Barometric pressure sensor malfunction
Neutral or clutch switch and related circuit
malfunction (MTX)
MAF sensor and related circuit malfunction
Knock sensor and related circuit malfunction
TP sensor and related circuit malfunction
TP sensor misadjustment (including looseness)
P/S pressure switch and related circuit
malfunction
Improper refrigerant charging amount
A/C relay (A/C control signal circuit malfunction
A/C compressor magnetic clutch malfunction
Condenser fan system malfunction
Improper load signal input
Clutch slippage
ATX related parts malfunction
VSS and related circuit malfunction
Improper ATF level
Brake dragging
Loose parts
Improper balance of wheels and tires
Drive line malfunction
Suspension malfunction
PATS operating (if equipped)
1 Melting of main or other fuses2 MIL illuminates x x x x x x x x3 Will not crankx4 Hard to start/long crank/erratic
start/erratic crankx
5 Engine stalls. After start/at idle x x x x6 Cranks normally but will not startx7 Slow return to idle8 Engine runs rough/rolling idle x x x x x x9 Fast idle/runs onx10 Low idle/stalls during deceleration x x x x x xEngine stalls/quits.Acceleration/cruisex x xx xx xxxEngine runs rough. Acceleration/cruisex x xx xx xxxMissesAcceleration/cruisex xx xx xxxBuck/jerk Acceleration/cruise
/decelerationx xx xx xxx
Hesitation/stumble Acceleration x x x x x x x x x
11
Surges Acceleration/cruise x x x x x x x x
12 Lack/loss of power Acceleration/cruise x x x x x x x x13 Knocking/pingingAcceleration/cruise x x x14 Poor fuel economy x x x x x15 Emission compliance x16 High oil consumption/leakage17 Cooling system
concernsOverheating x x x
18 Cooling system
concernsRuns cold x
19 Exhaust smoke20 Fuel odor (in engine compartment)21 Engine noisex22 Vibration concerns (engine)xxxx23 A/C does not work sufficiently. x x x24 A/C is always on or A/C compressorruns continuously.xx25 A/C is not cut off under WOT conditions x x26 Exhaust sulfur smell27 Constant voltage x x x x x x28 Spark plug condition x x29 ATX concernsUpshift/downshift/e
ngagementSee Section K, TROUBLESHOOTING
A6E39802004

F1–62
TROUBLESHOOTING
NO.14 POOR FUEL ECONOMYA6E398018881203
Diagnostic procedure
14 POOR FUEL ECONOMY
DESCRIPTIONFuel economy is unsatisfactory.
POSSIBLE CAUSE•Contaminated air cleaner element
•VIS malfunction (if equipped)
•Engine cooling system malfunction
•Improper ATF level (ATX)
•Weak spark
•Poor fuel quality
•Erratic or no signal from CMP sensor
•Clutch slippage (MTX)
•VTCS malfunction
•Improper variable valve timing control system operation (if equipped)
•Improper coolant level
•Inadequate fuel pressure
•Spark plug malfunction
•PCV valve malfunction
•Brake dragging
•Improper valve timing due to jumping out of timing belt
•Contaminated MAF sensor
•Improper engine compression
•Exhaust system clogging
•Improper electrically controlled 4WD system operation
Warning
The following troubleshooting flow chart contains fuel system diagnosis and repair
procedures. Read following warnings before performing fuel system services:
•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 REPAIR PROCEDURE” and “AFTER REPAIR PROCEDURE” described in this
manual.
Caution
•Disconnecting/connecting quick release connector without cleaning it may possibly 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.
STEP INSPECTION RESULTS ACTION
1 Inspect for following:
•Air cleaner element for contamination
•ATF level
•Fuel quality
•Coolant level
•Brake dragging
•Clutch slippage
Are all items okay?Yes Go to next step.
No Service as necessary.
Repeat Step 1.
2 Connect WDS or equivalent to DLC-2.
Retrieve any continuous memory, KOEO and
KOER DTCs.
Are there any DTCs displayed?YesDTC is displayed:
Go to appropriate DTC test.
NoNo DTC is displayed:
Go to next step.
3 Access ECT PID.
Drive vehicle while monitoring PID.
(See F1–33 PCM INSPECTION (4WD).)
Is PID within specification?Yes Go to next step.
No Inspect for coolant leakage, cooling fan and condenser
fan operations or thermostat operation.

TROUBLESHOOTING
F1–63
F1
End Of Sie
4 Is strong blue spark visible at each disconnected
high-tension lead while cranking engine?Yes Inspect for following:
•Spark plugs malfunction
•CMP sensor is improperly installed.
•Trigger wheel damage on camshaft
•Open or short circuit on CMP sensor
•Open or short circuit between CMP sensor and
PCM terminal 2J or 2M
Repair or replace malfunctioning parts.
If okay, go to next step.
No Inspect following:
•High-tension leads
•Ignition coil and connector
5 Install fuel pressure gauge between fuel pipe
and fuel distributor.
Start engine and run it at idle.
Measure fuel line pressure at idle.
Is fuel line pressure correct at idle?Yes Go to next step.
NoZero or low:
Inspect for clogged fuel line.
If okay, replace fuel pump unit
High:
Replace fuel pump unit.
6 Inspect for VTCS operation.
Does VTCS work properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
7Note
•The following test should be performed for
vehicles with variable valve timing control
system. Go to next step for vehicles
without variable valve timing control
system.
Inspect for variable valve timing control system
operation.
Does variable valve timing control system work
properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
8Note
•The following test should be performed for
vehicles with VIS. Go to next step for
vehicles without VIS.
Inspect for VIS operation.
Does VIS work properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
9 Remove and shake PCV valve.
Does PCV valve rattle?Yes Go to next step.
No Replace PCV valve.
10 Inspect for restriction in the exhaust system.
Is there any restriction?Yes Inspect exhaust system.
No Go to next step.
11 Inspect for contaminated MAF sensor.
Is there any contamination?Yes Go to next step.
No Inspect for cause.
12 Inspect MAF sensor for contamination.
Is there any contamination?Yes Replace MAF sensor.
No Go to Step 14. (2WD)
Go to next step. (4WD)
13 Inspect electrically controlled 4WD system
operation.
Is operation of electrically controlled 4WD
system okay?Yes Go to next step.
No Repair or replace malfunctioning parts.
14 Is engine compression correct? Yes Inspect valve timing.
No Inspect for cause.
15 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. STEP INSPECTION RESULTS ACTION