Page 173 of 558

MPI – Troubleshooting13-61
8. ACTUATOR TEST REFERENCE TABLE
Item
No.Inspection
itemDrive contentsInspection contentsNormal conditionInspection
procedure
No.Reference
page
01InjectorsCut fuel to No.
1 injectorEngine:
After having warmed
up/Engine is idling
Idling condition
becomes different
(becomes unsta
Code No.
4113-15
02Cut fuel to No.
2 injectorup/Engine is idling
(Cut the fuel supply to each
injector in turn and check
li d hi h d’ff
(becomes unsta-
ble, resulting in
engine stall).
03Cut fuel to No.
3 injector
j
cylinders which don’t affect
idling.)
04Cut fuel to No.
4 injector
07Fuel pumpFuel pump
operates and
fuel is recircu-
lated.Engine:
Cranking
Fuel
pump:
Forced
driving
Inspect ac-
cording to
Pinch the
return hose
with fingers
to feel the
pulse of the
fuel being
recirculated.Pulse is felt.Procedure
No. 2513-36
cording to
both the
above condi-
tions.
Listen near
the fuel tank
for the
sound of
fuel pump
operation.Sound of opera-
tion is heard.
09Fuel
pressure
control
valveSolenoid valve
turns from
OFF to ON.Ignition switch: ONSound of opera-
tion can be heard
when solenoid
valve is driven.Procedure
No. 3413-45
12Waste
gate
solenoid
valveSolenoid valve
turns from
OFF to ON.Ignition switch: ONSound of opera-
tion can be heard
when solenoid
valve is driven.Procedure
No. 3513-45
13Fuel pump
relay No.2Turn fuel
pump relay
No.2 from
OFF to ON.Ignition switch: ON
Listen to pump operation
sound near fuel tank.Sound of opera-
tion can be heard.Procedure
No. 2513-36
17Basic igni-
tion timingSet to ignition
timing adjust-
ment modeEngine: Idling
Timing light is set5BTDC––
Page 175 of 558

MPI – Troubleshooting13-63
ENGINE-ECU INSPECTION
TERMINAL VOLTAGES
Engine ECU connector
Terminal
No.Check itemCheck condition (Engine condition)Normal condition
1No.1 injectorWhile engine is idling after having been warmed up,
suddenly depress the accelerator pedal
Momentarily drops
slightlyfrom 1114V
14No.2 injector
suddenly depress the accelerator pedal.slightly from 11 – 14 V.
2No.3 injector
15No.4 injector
3Fuel pressure control
valve
Ignition switch: ONSystem voltage
valve
Engine: Cranking to idling (within about two minutes)0 – 3 V to sytem
voltage
4Stepper motor coil (A1)Engine: Immediately after engine has been started
f
or warming up
Changes repeatedly
f
rom system voltage
17Stepper motor coil (A2)
for warming upfrom system voltage
to 0 – 6 V and from 0
6 V to system5Stepper motor coil (B1)– 6 V to system
voltage.
18Stepper motor coil (B2)
6Secondary air control
solenoid valveIgnition switch: ONSystem voltage
8Fuel pump relayIgnition switch: ONSystem voltage
Engine: Idling0 – 3 V
10Power transistor unit
(A)Engine speed: 3,000 r/min0.3 – 3.0 V
23Power transistor unit
(B)
11Wastegate solenoid
valve
Ignition switch: ONSystem voltage
valve
Engine: At idle after having been warmed up (when
premium gasoline is used)0 – 3 V
12Power supplyIgnition switch: ONSystem voltage
25
19Air flow sensor reset
signal
Engine: Idling0 – 1 V
signal
Engine speed: 3,000 r/min6 – 9 V
20Fan motor relay (HI)
Fan not operating (coolant temperature: 90C or
below)System voltage
Fan at high speed (coolant temperature: 105C or
above)0 – 3 V
Page 176 of 558

MPI – Troubleshooting13-64
Terminal
No.Normal condition Check condition (Engine condition) Check item
20Radiator fan motor
relay (HI)
Radiator fan not operating (coolant temperature:
95C or below)System voltage
Radiator fan at high speed (coolant temperature:
105C or above)0 – 3 V
21Fan motor relay (LOW)
Fan not operating (coolant temperature: 95C or
below)System voltage
Fan at low speed (coolant temperature: 95 – 100C)0 – 3 V
21Radiator fan motor
relay (LOW)
Radiator fan not operating (coolant temperature:
95C or below)System voltage
Radiator fan at low speed (coolant temperature: 95
– 105C)0 – 3 V
22A/C relayEngine: Idling
A/C switch: OFF to ON (Compressor is being
driven.)System voltage, or 6
V or more instanta-
neously to 0 – 3 V
32A/C condenser fan
motor relay (HI)
A/C condenser fan not operating (A/C switch: ON,
coolant temperature: 105C or below)System voltage
A/C condenser fan at high speed (A/C switch: ON,
coolant temperature: 105C or above)0 – 3 V
33Alternator G terminalEngine: Warm, idle (radiator fan: OFF)
Headlamp: OFF to ON
Brake lamp: OFF to ON
Rear defogger switch: OFF to ONVoltage rises by 0.2 –
3.5 V.
34A/C condenser fan
motor relay (LOW)
A/C condenser fan not operating (A/C switch: OFF,
coolant temperature: 105C or below)System voltage
A/C condenser fan at low speed (A/C switch: OFF,
coolant temperature: 105C or above)0 – 3 V
36Engine warning lampIgnition switch: OFF → ON0 – 3 V → System
voltage (After several
seconds have
elapsed)
37Power steering fluid
pressure switchEngine: Idling after
warming upWhen steering wheel is
stationarySystem voltage
When steering wheel is
turned0 – 3 V
38Control relayIgnition switch: OFFSystem voltage
Ignition switch: ON0 – 3 V
39Fuel pump relay No.2While engine is idling, suddenly depress the
accelerator pedal.Momentarily rises
slightly from 0 to 3 V.
40Exhaust temperature
warning lampIgnition switch: OFF to ON0 – 3 V to system
voltage (After several
seconds have
elapsed)
Page 178 of 558
MPI – Troubleshooting13-66
Terminal
No.Normal condition Check condition (Engine condition) Check item
87Idle position switchIgnition switch: ONSet throttle valve to idle
position0 – 1 V
Slightly open throttle
valve4 V or more
88Camshaft position
sensor
Engine: Cranking0.4 – 3.0 V
sensor
Engine: Idle speed0.5 – 2.0 V
89Crank angle sensorEngine: Cranking0.4 – 4.0 V
Engine: Idle speed1.5 – 2.5 V
90Air flow sensorEngine: Idle speed2.2 – 3.2 V
Engine speed: 2,000 r/min
Page 179 of 558

MPI – Troubleshooting13-67
RESISTANCE AND CONTINUITY BETWEEN HARNESS SIDE CONNECTORS AND TERMINALS
Engine-ECU Harness Side Connector Terminal Arrangement
Terminal No.Inspection itemNormal condition (Check condition)
1 – 12No.1 injector2 – 3 Ω (At 20C)
14 – 12No.2 injector
2 – 12No.3 injector
15 – 12No.4 injector
3 – 12Fuel pressure control valve28 – 36 Ω (At 20C)
4 – 12Stepper motor coil (A1)28 – 33 Ω (At 20C)
17 – 12Stepper motor coil (A2)
5 – 12Stepper motor coil (B1)
18 – 12Stepper motor coil (B2)
6 – 12Secondary air control solenoid valve28 – 36 Ω (At 20C)
11 – 12Wastegate solenoid valve62 – 74 Ω (At 20C)
60 – 12Oxygen sensor heater
11 – 18 Ω (at 20C)
13 – Body earthEngine-ECU earthContinuity established (0 Ω)
26 – Body earth
72 – 92Intake air temperature sensor5.3 – 6.7 kΩ (When intake air temperature is 0C)
2.3 – 3.0 kΩ (When intake air temperature is 20C)
1.0 – 1.5 kΩ (When intake air temperature is 40C)
0.30 – 0.42 kΩ (When intake air temperature is 80C)
74 – 77High temperature sensor3 Ω or less
83 – 92Engine coolant temperature sensor5.1 – 6.5 kΩ (When coolant temperature is 0C)
2.1 – 2.7 kΩ (When coolant temperature is 20C)
0.9 – 1.3 kΩ (When coolant temperature is 40C)
0.26 – 0.36 kΩ (When coolant temperature is 80C)
87 – 92Idle position switchContinuity established (when throttle valve is at idle
position)
No continuity (when throttle valve is slightly open)
91 – Body earth–Continuity established
Page 216 of 558

REAR AXLE – Troubleshooting 27-20
5. INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptomInspection
procedure No.Ref. page
Communication between MUT-II and the whole system is not possible.127-20
Communicatio between MUT-II and AYC-ECU is not possible.227-21
AYC warning lamp does not light up when the ignition key is turned to “ON” (engine
stationary).327-22
AYC warning lamp remains lit up after the engine has started.427-23
AYC is inoperative.
Unable to start or accelerate on slippery road surfaces.527-23
Rear tires are noisy during low-speed cornering.
Vehicle skews.627-24
6. INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
Communication between MUT-II and the whole system is
not possible.
Probable cause
The cause may be a malfunction of the power supply circuit or the ground circuit
of the diagnosis connector.Defective diagnosis connector
Defective harness or connector
NG
Check and repair the harness between
power supply and diagnosis connector.
OK
Check the trouble symptom.
NG
Check and repair the harness between
body ground and diagnosis connector.
OK
Check the trouble symptom.
OK
Replace MUT-II.
Check the following connectors:
B-22, B-50NG
Repair
OK
Measure at B-22 diagnosis connector.
Disconnect the connector and
measure at the harness side.
Continuity across 4/5 and body
ground
OK:ConductingNG
Measure at B-22 diagnosis combina-
tion meter connector.
Voltage across 16 and body ground
OK:System voltageNGCheck the following connectors:
B-22, B-49, B-75, B-73NG
Repair
Page 218 of 558

REAR AXLE – Troubleshooting 27-22
INSPECTION PROCEDURE 3
AYC warning lamp does not light up when the ignition key
is turned to “ON” (engine stationary).
Probable cause
The lamp power supply circuit is probably open-circuited, lamp bulb is out, or the
circuit between AYC warning lamp and AYC-ECU or AYC-ECU itself is defective.Blown fuse
AYC warning lamp out
Defective harness or connector
Defective AYC-ECU
NG
Check and repair the harness between
ignition switch (IG
2) and AYC warning
lamp.
OK
Check the trouble symptom.
OK
Replace combination meter.
NG
Check the harness between AYC
warning lamp and AYC-ECU.NG
Repair
OK
Check the trouble symptom.OK
Replace AYC-ECU.
OK
Check the following connectors:
B-96, B-94, B-08NG
Repair
OK
Measure at B-96 AYC-ECU connector.
Disconnect the connector and
measure at the harness side.
Ignition switch: ON
Warning lamp when 36 is grounded
to body
OK:Lit upNGCheck the lamp bulb.NG
Replace
Measure at B-08 combination meter
connector.
Disconnect the connector and
measure at the harness side.
Ignition switch: ON
Voltage across 48 and body ground
OK:Symptom voltageNGCheck the following connectors:
B-08, B-74, B-76NG
Repair
Page 234 of 558

REAR AXLE – On-vehicle Service 27-38
Waveform Observation Points
SymptomProbable causeAction
Waveform amplitude is too small, or no
waveform.Defective wheel speed sensorReplace sensor.
Waveform amplitude varies greatly. (No
problem ifthe smallest amplitude is 100
Excessive axle hub lateral and radial runoutReplace hub.
problem if the smallest amplitude is 100
mV or more)Poor AYC-ECU groundingRepair.
Noise on waveform or disturbed
waveform
Open-circuited sensorReplace sensor.
waveform
Open-circuited harnessRepair harness.
Improperly mounted wheel speed sensorCorrect sensor installation.
Missing or collapsed ABS rotor toothReplace ABS rotor.
Caution
Since the wheel speed sensor cable follows the movement of the front or rear suspension, it
may be open-circuited only when the vehicle is run on rough roads and not on ordinary road.
The wheel speed sensor output voltage waveform should therefore be checked also by rocking
the sensor harness so that driving on rough roads may be simulated.
ACTION WHEN BATTERY RUNS OUT
When the engine is started using a booster cable where the
battery has completely run down and you attempt to start
the vehicle without waiting for the battery to recover a certain
charge, the engine can misfire and you just cannot start to
move it. In such cases, charge the battery sufficiently; or,
remove the AYC fusible link from the engine compartment
relay box to make AYC inactive before attempting to start
the vehicle. When the fusible link is removed, the AYC warning
lamp lights up. After the battery has been recharged, fit the
fusible link back again and start the engine to ensure that
the AYC warning lamp is off.AYC fusible link