MPI -Troubleshooting13A-29
Code No. P0141 Oxygen sensor heater (rear) systemProbable cause
Inspection Range
DThe engine coolant water temperature is approximately more than 20_C.
DThe oxygen sensor heater (rear) is ON.
DThe engine speed is more than 50 r/min.
DA/C relay: OFF, radiator fan: OFF
DThe battery voltage is 11 - 16 V.
Evaluation Conditions
DThe oxygen sensor heater (rear) current is less than 0.2 A or more than 3.5
A for 4 seconds.DOxygen sensor heater (rear) malfunction
DOxygen sensor heater (rear) circuit disconnection,
short-circuit, or connector contact defect
DEngine-ECU malfunction
OK
Intermittent malfunction
(Refer to GROUP 00 - Points to Note
for Intermittent Malfunctions.)
OK
Check the trouble symptom.NGReplace the engine-ECU.
OK
Check the harness between the
oxygen sensor (rear) and engine-ECU.
DCheck for damage of the earth
wire.NG
Repair
OK
Check the harness between the
oxygen sensor (rear) and engine
control relay.
DCheck for damage of the power
cable.NG
Repair
OK
Check the following connector:
B-11X, C-108NG
Repair
OK
Replace the engine-ECU.NG
OK
Check the harness between the
oxygen sensor (rear) and engine-ECU.
DCheck for disconnection and
short-circuit of the earth wire.Repair
OK
Measure at the C-118 engine-ECU
connector.
DMeasure the engine-ECU terminal
voltage.
DIgnition switch: ON
DVoltage between terminal No. 54
and earth.
OK:System voltageNGCheck the following connector:
C-118NG
Repair
OK
Check and repair the harness between
the oxygen sensor (rear) and engine
control relay.
DCheck the power cable for
disconnection and short-circuit.
OK
Measure at the D-22 oxygen sensor
(rear) connector.
DDisconnect the connector, and
measure at the harness.
DIgnition switch: ON
DVoltage between terminal No. 3
and earth
OK:System voltageNGCheck the following connector:
B-11XNG
Repair
OK
Measure at the D-22 oxygen sensor
(rear) connector.
DDisconnect the connector, and
measure at the sensor.
DResistance between terminal No.
3 and terminal No. 4.
OK:11 - 1 8ΩNGReplace the oxygen sensor (rear).
Check the following connector:
D-22NG
Repair
MPI -Troubleshooting13A-44
Code No. P0505 Idle speed control systemProbable cause
Range of Check
DVehicle speed has reached 1.5 Km/h at least once.
DUnder the closed loop idle speed control.
Set Conditions
DActual idle speed has continued to be higher than the target idle speed by 300
r/min or more for 10 seconds.
Range fo Check
DVehicle speed has reached 1.5 km/h at least once.
DDuring idle speed closed loop control.
DThe highest temperature at the last drive is 45_C or less.
DEngine coolant temperature is approximately 80_C or more.
DBattery voltage is 10 V or more.
DBarometric pressure is 76 kPa or higher.
DIntake air temperature is - 10_C or more.
Set Conitions
DActual idle speed has been minimum 200 r/min higher than the target idle speed
for 10 seconds.
Range of Check
DDuring idle speed closed loop control.
DEngine coolant temperature is approximately 80_C or higher.
DBattery voltage is 10 V or higher.
DPower steering switch is off.
DVolumetric efficiency is 40 % or lower.
DBarometric pressure is 76 kPa or higher.
DIntake air temperature is - 10_C or more.
Set Conitions
DActual idle speed has been minimum 100 r/min higher than the target idle speed
for 10 seconds.DMalfunction of idle speed control servo
DOpen or short circuit in the idle speed control servo
circuit or loose connector contact
DMalfunction of engine-ECU
MPI -Troubleshooting13A-46
Code No. P0551 Power steering fluid pressure switch
systemProbable cause
Range of Check
DIntake air temperature is - 10_C or higher.
DBarometric pressure is 76 kPa or more.
DEngine coolant temperature is 30_C or more.
DRepeat the *1 drive and *2 stop ten times or more.
*1: Engine speed is 2500 r/min or higher, volumetric efficiency is 55 % or higher and
vehicle speed is 5 km/h or higher for 4 seconds or more.
*2: Vehicle speed is 1.5 km/h or lower.
Set Conditions
DPower steering fluid pressure switch remains on.DPower steering fliud pressure switch failed
DOpen or short circuit in the power steering fluid
pressure switch circuit or loose conector contact
DMulfunction of engine-ECU
NG
OKOK
NGCheck the following connectors:
C-122, C-136
NG
OKNG
OK
Check the harness between the
power steering fluid pressure switch
and engine-ECU.
DCheck for short-circuit of the
output cable.Repair Repair
OKIntermittent malfunction (Refer to GROUP 00 - Points to Note
for Intermittent Malfunctions.)
NG
OK
Measure at the A-48 power steering
fluid pressure switch connector.
DDisconnect the connector to
measure at the harness side.
DIgnition switch: ON
DVoltage between terminal No. 1
and earth
OK:System voltageNGMeasure at the C-122 engine-ECU
connector.
DMeasure the engine-ECU terminal
voltage.
DIgnition switch: ON
DVoltage between terminal No. 37
and earth
OK:System voltage
OK
NG
Replace the engine-ECU.
MUT-IIData list
DNo. 27: Power steering fluid pressure switch (Refer to
P.13A-103.)
OK
Check the following connector:A-48NG
Repair
NG
Repair OK
Check the following connector:
C-126, C-136
Check and repair the harness
between the power steering fluid
pressure switch and engine-ECU.
DCheck for disconnection of the
output cable.
Replace the engine-ECU.
OK
NG
MUT-IIData list
DNo. 27: Power steering fluid
pressure switch (Refer to
P.13A-103.)Intermittent malfunction (Refer to
GROUP 00 - Points to Note for
Intermittent Malfunctions.)
Measure at the C-122 engine-ECU connector.
DMeasure the engine-ECU terminal voltage.
DEngine: Idling
DVoltage between terminal No. 37 and earth
DSteering wheel: Stationary state
OK:System voltage
DSteering wheel: Steered state
OK:1 V or less
OK
Replace the power steering fluid
pressure switch.Repair
Check the following connector:
C-122NG
Repair
Check the following connector:C-122
Check the harness between the
power steering fluid pressure switch
and engine-ECU.
DCheck for damage of the output
cable.OK
Repair NG
MPI -Troubleshooting13A-61
Inspection Procedure 7
Starting disabled (Initial combustion occurs but is
incomplete.), improper starting (Starting time is long.)
Probable cause
Causes shown on right are suspected.DBattery malfunction
DIgnition system malfunction
DFuel system malfunction
DIntake system malfunction
DEGR valve malfunction
DTiming belt malfunction
DImproper compression pressure
DEngine-ECU malfunction
OK
To the next page
OK
Check and repair the harness between
the engine-ECU and earth joint.
DCheck for disconnection and
damage of the earth cable.
(2) NGCheck the following connector:
C-126NG
Repair
NG
Replace the engine-ECU.
OK
Check the trouble symptoms.OKIntermittent malfunction
(Refer to GROUP 00 - Points to Note
for Intermittent Malfunctions.) NG
OK
Check the harness between the
engine-ECU and battery.
DCheck for disconnection,
short-circuit and damage of the
power cable.Repair
OK
Measure at the C-115 and C-126 en-
gine-ECU connectors.
DMeasure the engine-ECU terminal
voltage.
(1) Voltage between terminal No. 80
and earth
OK:System voltage
(2) Voltage between terminal No. 13
and earth
Voltage between terminal No. 26
and earth
(Ignition switch: ON)
OK:0.5 V or less(1) NGCheck the following connectors:
C-115, C-129, C-05, C-135NG
Repair
OK
Check the timing marks on the timing belt.NGAlign the timing marks on the timing belt.
OK
Check the air intake from the intake hose and intake manifold.NG
Repair
NO
MUT-IIData list
DNo. 13: Intake air temperature sensor
DNo. 21: Engine coolant temperature sensor
DNo. 25: Barometric pressure sensor
(Refer to P.13A-102.)
Proceed to OK if all service data values are correct.
Proceed to NG if there is even one abnormal service data value.NGRefer to inspections for diagnosis code of sensor showing abnormal
service data. (Refer to P.13A-12.)
OK
MUT-IISelf-Diag code
DIs a diagnosis code output?YESINSPECTION CHART FOR DIAGNOSIS CODE
(Refer to P.13A-12.)
NO
Check the battery. (Refer to GROUP 54 - Battery.)NGReplace the battery.
Has the battery terminal been disconnected recently?YESAfter warming up the engine, idle for approximately 10 minutes.
MPI -Troubleshooting13A-63
Inspection Procedure 8
Unstable idling (Rough idling, hunting), inappropriate
idling speed (High or low idling speed), engine stalls (Die
out) during idling
Probable cause
Causes shown on right are suspected.DIdle speed control system malfunction
DAir/fuel ratio control system malfunction
DIgnition system malfunction
DFuel system malfunction
DIntake and exhaust system malfunction
DExhaust gas purifier system malfunction
DThrottle valve malfunction
DTiming belt malfunction
DImproper compression pressure
DEngine-ECU malfunction
OK
To the next page
OK
MUT-IIData list
DNo. 11: Oxygen sensor (front) (Refer to P.13A-102.)NGCheck the Code No. P0130: Oxygen sensor (front) system.
(Refer to P.13A-24.)
OK
Check the throttle body (throttle valve section) for contamination.NGClean the throttle body (throttle valve section).
(Refer to P.13A-126.)
OK
Check the air intake from the intake hose and intake manifold.NG
Repair
OK
Check the timing marks on the timing belt.NGAlign the timing marks on the timing belt.
OK
MUT-IIData list
DNo. 27: Power steering fluid pressure switch
(Refer to P.13A-103.)NGCheck the Power steering fluid pressure switch system. (Refer to
P.13A-51, PROCEDURE FOR DAIGNOSIS CODE P0551)
OK
MUT-IIData list
DNo. 45: Idle speed control servo position (Refer to P.13A-105.)NGCheck the Idle speed control servo (stepper motor) system. (Refer
to P.13A - 49 PROCEDURE FOR DIAGNOSIS CODE P0505)
NO
MUT-IIData list
DNo. 12: Air flow sensor
DNo. 13: Intake air temperature sensor
DNo. 14: Throttle position sensor
DNo. 21: Engine coolant temperature sensor
DNo. 25: Barometric pressure sensor
(Refer to P.13A-102.)
Proceed to OK if all service data values are correct.
Proceed to NG if there is even one abnormal service data value.NGRefer to inspections for diagnosis code of sensor showing abnormal
service data. (Refer to P.13A-12.)
NO
MUT-IISelf-Diag code
DIs a diagnosis code output?YESINSPECTION CHART FOR DIAGNOSIS CODE
(Refer to P.13A-12.)
Has the battery terminal been disconnected recently?YESAfter warming up the engine, idle for approximately 10 minutes.
MPI -Troubleshooting13A-68
Inspection Procedure 11
Pulsation (Hesitation, sag), poor acceleration, stumbling,
surging
Probable cause
Causes shown on right are suspected.DAir/fuel ratio control system malfunction
DIgnition system malfunction
DFuel system malfunction
DIntake and exhaust system malfunction
DExhaust gas purifier system malfunction
DImproper compression pressure
DTurbocharger system malfunction
OK
To the next page
OK
MUT-IIData list
DNo. 59: Oxygen sensor (rear) (Refer to P.13A-105.)
(Refer to P.13A-27.)
OK
MUT-IIData list
DNo. 11: Oxygen sensor (front) (Refer to P.13A-102.)NGCheck the Code No. P0130: Oxygen sensor (front) system.
(Refer to P.13A-24.)
OK
Check the EGR valve for sticking.
(Refer to GROUP 17 - Exhaust Gas Purifier Check.)NGReplace the EGR valve.
OK
Check the EGR control solenoid valve.
(Refer to GROUP 17 - Exhaust Gas Purifier Check.)NGReplace the EGR control solenoid valve.
OK
Check the purge control solenoid valve.
(Refer to GROUP 17 - Exhaust Gas Purifier Check.)NGReplace the purge control solenoid valve.
OK
MUT-IIData list
DNo. 13: Intake air temperature sensor
DNo. 14: Throttle position sensor
DNo. 21: Engine coolant temperature sensor
DNo. 25: Barometric pressure sensor
(Refer to P.13A-102.)
Proceed to OK if all service data values are correct.
Proceed to NG if there is even one abnormal service data value.NGRefer to inspections for diagnosis code of sensor showing
abnormal service data. (Refer to P.13A-12.)
OK
Check the injector operation sound. (Use sound scope.)NGCheck the Code No. P0201 - 204: Injector system for faulty
cylinder.
NO
Check the ignition timing.
(Refer to GROUP 11 - Engine Adjustment.)NGCheck mounting state of crank angle sensor and timing belt cover.
MUT-IISelf-Diag code
DIs a diagnosis code output?YESINSPECTION CHART FOR DIAGNOSIS CODE
(Refer to P.13A-12.)
MPI -Troubleshooting13A-75
Inspection Procedure 17
Abnormal odor, white smoke, black smoke, high CO or HC
concentration when idling
Probable cause
Causes shown on right are suspected.DAir/fuel ratio control system malfunction
DIgnition system malfunction
DFuel system malfunction
DIntake and exhaust system malfunction
DExhaust gas purifier system malfunction
DImproper compression pressure
DCatalyst defect
DEngine-ECU malfunction
OK
To the next page
OK
Check the fuel pressure. (Refer to P.13A-128.)
OK
MUT-IIData list
DNo. 59: Oxygen sensor (rear)
(Refer to P.13A-105.)NGCheck the Code No. P0136: Oxygen sensor (rear) system.
(Refer to P.13A-27.)
OK
MUT-IIData list
DNo. 11: Oxygen sensor (front) (Refer to P.13A-102.)NGCheck the Code No. P0130: Oxygen sensor (front) system.
(Refer to P.13A-24.)
OK
Check for exhaust gas leaks from exhaust manifold.NG
Repair
OK
Check the air intake from the intake hose and intake manifold.NG
Repair
OK
MUT-IIData list
DNo. 12: Air flow sensor
DNo. 13: Intake air temperature sensor
DNo. 21: Engien coolant temperature sensor
DNo. 25: Barometric pressure sensor
(Refer to P.13A-102.)
Proceed to OK if all service data values are correct.
Proceed to NG if there is even one abnormal service data value.NGRefer to inspections for diagnosis code of sensor showing
abnormal service data. (Refer to P.13A-102.)
OK
Check the ignition timing.
(Refer to GROUP 11 - Engine Adjustment.)NGCheck the Inspection Procedure 15: Deviation of ignition interval
(Refer to P.13A-73.)
NO
MUT-IIActuator test
DNo. 01: No. 1 injector
DNo. 02: No. 2 injector
DNo. 03: No. 3 injector
DNo. 04: No. 4 injector
OK:The idling state changes.
DProceed to NG if the cylinder (NG cylinder) for which the idling
state did not change when injector was stopped is pinpointed.
DProceed to OK if all cylinders are OK, or if the NG cylinder
cannot be pinpointed.NGCheck the Code No. P0201: No. 1 injector system, P0202: No. 2
injector system, P0203: No. 3 injector system and P0204: No. 4
injector system. (Refer to P.13A-30, 31, 32, 33.)
MUT-IISelf-Diag code
DIs a diagnosis code output?YESINSPECTION CHART FOR DIAGNOSIS CODE
(Refer to P.13A-12.)
MPI -Troubleshooting13A-79
Inspection Procedure 19
Overheating
Probable cause
Causes shown on right are suspected.DEngine coolant insufficient or deteriorated
DFan controller malfunction
DEngine coolant temperature sensor malfunction
DThermostat malfunction
DWater pump malfunction
DCondenser fan relay malfunction
DRadiator core malfunction
DEngine-ECU malfunction
NO
NG
Replace or replenish the engine coolant.
OK
Replace the radiator core.
OK
Check the water pump. (Refer to GROUP 14 - Water pump.)NGReplace the water pump.
OK
Check the thermostat. (Refer to GROUP 14 - Thermostat.)NGReplace the thermostat.
OK
MUT-IIData list
DNo. 21: Engine coolant temperaure sensor
OK:Approximately the same as the ambient temperature
when cooled.
Between 80 - 120_C when hot.NGCheck the Code No. P0115: Engine coolant temperature
sensor system. (Refer to P.13A-19.)
MUT-IIData list
21 Engine coolant temperature sensor (Refer to P.13A-102.)
OK
MUT-IIActuator Test
DNo. 37: Condenser fan (HI)
DNo. 38: Condenser fan (LOW)
DIgnition switch: ON
OK:Condenser fan rotates (low speed).
OK:Condenser fan rotates (high speed).NGCheck the Inspection Procedure 25: Condenser fan control
relay system. (Refer to P.13A-89.)
MUT-IIActuator Test
DNo. 21: Fan controller
DIgnition switch: ON
OK:Radiator fan rotates.NGCheck the Inspection Procedure 24: Radiator fan control relay
system. (Refer to P.13A-87.)
OK
Check the engine coolant.
(Refer to GROUP 14 - On-vehicle Service.)
If the engine coolant level is low, check whether the engine
coolant has leaked, and repair if required.
MUT-IISelf-Diag Code
Is a diagnosis code output?YESINSPECTION CHART FOR DIAGNOSIS CODE (Refer to
P.13A-12.)