1998 TOYOTA LAND CRUISER ESP

2004 LAND CRUISER (EWD548U)
192Multiplex Communication System
The multiplex communication system communicates among the body ECU, theft deterrent ECU, power window master SW,
power window control SW front RH, power window control SW rear LH, power window control SW rear RH, center airbag
sensor assembly and tilt and telescopic ECU, among the combination meter, engine control module, A/C control assembly
and gateway ECU and controls the following systems according to the signals from respective sensors or switches.
For details, please refer to the new car features and/or the repair manual.
Body ECU
11, 12-Ground : Always approx. 12 volts
22-Ground : Approx. 12 volts with ignition SW at ACC or ON position
10-Ground : Approx. 12 volts with ignition SW at ON or ST position
4, 16-Ground : Always continuity
: Parts Location
CodeSee PageCodeSee PageCodeSee Page
A3170D1872J1471
A45A70D1972J2272
A47C70D2072M272
B272D2172M5A71
B372D2272M9B71
B472D2372P169
B574D2472P873
B7A70D2772P1273
B8B70E368P1473
B9C70E8D70P1573
C12A70E9E70P1673
C13B70F168P1773
C14C70F268P1873
C15D70F1072P1973
C1670F1172P2073
C2670F1568R671
D2A68G168R2773
D3B68G470S571
D770H169T169
D1072H269T571
D1172H369T771
D1272H469T1071
D1372J371U171
D1472J671V269
D1572J971V673
D1672J1071V773
D1772J1371Z171
System Outline
Service Hints

2004 LAND CRUISER (EWD548U)
201
When the ignition SW is turned on, the current flows from the WASHER fuse to washer motor TERMINAL 2, and the current
flows from the RR WIPER fuse to rear wiper relay TERMINAL 3, and the rear wiper motor TERMINAL 1 respectively.
1. Rear Wiper Normal Operation
When the ignition SW is turned on, and the rear wiper and washer SW is turned to ON position, the current flows from the
rear wiper relay TERMINAL 3 to TERMINAL 6 to the rear wiper and washer SW TERMINAL 10 to TERMINAL 2 to
GROUND, and turns on the rear wiper relay. As a result, the current flows from the rear wiper relay TERMINAL 3 to
TERMINAL 4 to the rear wiper motor TERMINAL 3 to TERMINAL 2 to GROUND, and operates the rear wiper.
2. Rear Wiper Intermittent Operation
When the ignition SW is turned on, and the rear wiper and washer SW is turned to INT position, the current flows from the
rear wiper relay TERMINAL 3 to TERMINAL 2 to the rear wiper and washer SW TERMINAL 13 to TERMINAL 2 to
GROUND, and the intermittent circuit in the rear wiper relay is controlled to operate the wiper intermittently.
3. Washer Operation
When the ignition SW is turned on, and the rear wiper and washer SW is turned from OFF to WASH position, the current
flows from the WASHER fuse to the washer motor TERMINAL 2 to TERMINAL 1 to the rear wiper and washer SW
TERMINAL 12 to TERMINAL 2 to GROUND. This activates the washer motor, and the window washer emits a water spray.
When the rear wiper and washer SW is turned to ON position, the window washer emits a water spray during rear wiper
normal operation.
W1 Washer Motor
2-Ground : Approx. 12 volts with ignition SW at ON or ST position
1-Ground : Continuity with rear wiper and washer SW at WASH position
R30 Rear Wiper Motor
1-Ground : Approx. 12 volts with ignition SW at ON or ST position
2-Ground : Always continuity
: Parts Location
CodeSee PageCodeSee PageCodeSee Page
C1970J2272R3173
J371R3073W169
:Junction Block and Wire Harness Connector
CodeSee PageJunction Block and Wire Harness (Connector Location)
1A24Engine Room Main Wire and Engine Room J/B (Engine Compartment Left)
1B24Engine Room No.2 Wire and Engine Room J/B (Engine Compartment Left)
2A28Engine Room No.2 Wire and Cowl Side J/B LH (Left Kick Panel)
2D28Dash Wire and Cowl Side J/B LH (Left Kick Panel)
2K28Floor No.1 Wire and Cowl Side J/B LH (Left Kick Panel)
3A40Engine Room No.2 Wire and Cowl Side J/B RH (Right Kick Panel)
3E40Dash Wire and Cowl Side J/B RH (Right Kick Panel)
:Connector Joining Wire Harness and Wire Harness
CodeSee PageJoining Wire Harness and Wire Harness (Connector Location)
EA276Engine Room Main Wire and Engine Room No.2 Wire (Engine Compartment Right)
ID478Dash Wire and Floor No.1 Wire (Left Kick Panel)
II380Dash Wire and Column Wire (Near the Ignition SW)
BH186Pillar No 1 Wire and Back Door Upper Wire (Left Side of Back Door)BH286Pillar No.1 Wire and Back Door Upper Wire (Left Side of Back Door)
BP388Pillar No.1 Wire and Floor No.1 Wire (Left Rear Side Quarter Panel)
System Outline
Service Hints

2004 LAND CRUISER (EWD548U)
218Electronically Controlled Transmission and A/T Indicator
Previous automatic transmissions have selected each gear shift using mechanically controlled throttle hydraulic pressure,
governor hydraulic pressure and lock-up hydraulic pressure. The electronically controlled transmission, however, electrically
controls the line pressure, throttle pressure, lock-up pressure and accumulator pressure etc. through the solenoid valve. The
electronically controlled transmission is a system which precisely controls gear shift timing and lock-up timing in response to
the vehicle's driving conditions and the engine condition detected by various sensors. It makes smooth driving possible by
shift selection for each gear which is the most appropriate to the driving conditions at that time, and by preventing downing,
squat and gear shift shock when starting off.
1. Gear Shift Operation
When driving, the engine warm up condition is input as a signal to TERMINAL THW of the engine control module from the
engine coolant temp. sensor and the vehicle speed signal from vehicle speed sensor is input to TERMINAL SP2+ of the
engine control module. At the same time, the throttle valve opening signal from the throttle position sensor is input to
TERMINALS VTA1 and VTA2 of the engine control module as throttle angle signal.
Based on these signals, the engine control module selects the best shift position for the driving conditions and sends current
to the electronically controlled transmission solenoid.
2. Line Hydraulic Pressure Control
The engine control module adjusts the line hydraulic pressure to the optimal level by controlling TERMINAL SLT+ of the
module according to the engine torque data. This realizes the smooth gear shifting.
3. High Response Gear Shifting Control
The engine control module performs the high response engine torque up control to control the ignition-timing lag as well as
opening the electronic throttle when shifting down. By doing this, the gear shifting is performed in a short period of time.
Moreover, the engine control module uses the orifice switching control, which optimizes the speed of applying and reducing
the hydraulic pressure. And it realizes the fine shifting condition by applying and reducing hydraulic pressure slowly when
the gear shifting shock is important and quickly when the high response is required.
4. Clutch Hydraulic Pressure Control
The engine control module controls the clutch operation in the optimal timing and with the best hydraulic pressure according
to the engine torque data and the number of the clutch revolution
5. Lock-Up and Flexible Lock-Up Control
The engine control module carries out the lock-up control by controlling the TERMINAL SLU+ of the module according to
the shift position, vehicle speed, throttle opening degree and running conditions. The engine control module also steadily
keeps applying the lock-up clutch a delicate slippage to improve the transmission efficiency (Fuel efficiency) of the torque
converter.
6. Stop Light SW Circuit
If the brake pedal is depressed (Stop light SW on) when driving in lock-up condition, a signal is input to TERMINAL STP of
the engine control module. The engine control module operates and cuts the current to the solenoid to release lock-up.
7. Ai-Shift Control
The engine control module judges whether the road is downslope or upslope by detecting the throttle opening degree or the
vehicle's speed. Moreover it can expect the winding roads by detecting the turning condition of the vehicle. The engine
control module keeps unnecessary shifting up from the fourth gear from operating and carries out the automatic shifting
down to the third gear in order to control the vehicle running according to the road conditions. The engine control module
also reads the driver's intention during driving from his (her) accelerating operation and the running conditions of the vehicle.
As a result of that, ideal shifting patters for each driver are automatically selected without any switching operations.
8. Electronically Controlled Transmission Pattern Select SW Circuit
When the electronically controlled transmission pattern select SW is switched to PWR, a signal is input to TERMINAL PWR
of the engine control module. This enables shift-up and shift-down at a higher speed range.
9. Transfer Shift Operation
When the transfer shift lever is moved to L position, a signal is input into TERMINAL L4 of the engine control module.
In addition when the transfer shift lever is moved to N position a signal is input to engine control module TERMINAL TFN.
The engine control module detects the transfer condition through this.
System Outline

2004 LAND CRUISER (EWD548U)
234VSC
1. ABS Operation
If the brake pedal is depressed suddenly, the ABS controls the hydraulic pressure of the wheel cylinders for all the four
wheels to automatically avoid wheel locking and ensure the directional and steering stability of the vehicle. If the brake pedal
is depressed suddenly, the ABS & BA & TRAC & VSC ECU controls the solenoids in the actuators using the signals from the
sensors to move the brake fluid to the reservoir in order to release the braking pressure applied to the wheel cylinder. If the
ABS & BA & TRAC & VSC ECU detects that the fluid pressure in the wheel cylinder is insufficient, the ECU controls the
solenoids in the actuators to increase the braking pressure.
2. Traction Control Operation
The traction control system controls the engine torque, the hydraulic pressure of the driving wheel cylinders, slipping of the
wheels which may occur at start or acceleration of the vehicle, to ensure an optimal driving power and vehicle stability
corresponding to the road conditions.
3. VSC Operation
Unexpected road conditions, vehicle speed, emergency situation, and any other external factors may cause large under- or
over-steering of the vehicle. If this occurs, the VSC system automatically controls the engine power and wheel brakes to
reduce the under- or over-steering.
To reduce large over-steering :
If the VSC system determines that the over-steering is large, it activates the brakes for the outer turning wheels depending
on the degree of the over-steering to produce the moment toward the outside of the vehicle and reduce the over-steering.
To reduce large under-steering :
If the VSC system determines that the under-steering is large, it controls the engine power and activates the rear wheel
brakes to reduce the under-steering.
VSC indicator light
If an error occurs in the VSC system, the VSC indicator lights up to warn the driver.
4. Traction Mode and VSC Function
When the center differential of the transfer is locked, the VSC function is turned off. At this time, the VSC OFF indicator light
in the combination meter will come on, and informs the driver that the VSC function is OFF.
5. Mutual System Control
To efficiently operate the VSC system at its optimal level, the VSC system and other control systems are mutually controlled
while the VSC system is being operated.
Engine throttle control
The engine power does not interfere with the VSC brake control by controlling the opening of the throttle and reducing the
engine output.
Engine control and electronically controlled transmission control
The strong braking force does not interfere with the braking force control of the VSC system by turning off the accel. and
reducing changes in the driving torque at shift-down.
VSC system operation indication
The slip indicator light flashes and the buzzer sounds intermittently to warn the driver that the current road is slippery, while
the VSC system is being operated.
6. Fail Safe Function
If an error occurs in the ABS & BA & TRAC & VSC ECU, sensor signals, and/or actuators, the ABS & BA & TRAC & VSC
ECU inhibits the brake actuator control and inputs the error signal to the engine control module. According to the error signal,
the brake actuator turns off the solenoid and the engine control module rejects any electronically controlled throttle open
request from the VSC system. As a result, the vehicle functions without the ABS, BA, TRAC, and VSC systems.
System Outline

2004 LAND CRUISER (EWD548U)
278Wireless Door Lock Control
In this system, the door control receiver receivers weak radio wave transmitted from the transmitter built-into the ignition key,
and outputs a signal to the body ECU. Accordingly, all the doors are can be locked and unlocked by remote control.
1. Normal Operation
*Lock operation
When the lock SW on the transmitter is pressed, all the doors are locked.
*Unlock operation
When the unlock SW on the transmitter is pressed once, only the driver door is unlocked. When the unlock SW is pressed
again within 3 seconds, all the doors are unlocked.
2. Auto Lock Function
When the door is not actually opened within 30 seconds after the door has been unlocked by the unlock SW on the
transmitter, all the doors are automatically locked. If any of the following conditions are detected, the wireless door lock does
not function.
*Any door is opened.
*The ignition key is inserted into the ignition SW.
*When the unlock detection SW of all the doors are locked.
3. Wireless Door Lock Stop Function
If any of the following conditions are detected, the wireless door lock does not function.
Lock operation
*When any door is open (Door courtesy SW on)
*The ignition key is inserted into the ignition SW (Unlock warning SW on)
*Ignition SW is on
Unlock operation
*Ignition SW is on
4. Visual Confirmation of Lock or Unlock
During lock operation, when the door control receiver receives a lock signal from the door unlock detection SW, the turn
signal light is flashed once. During unlock operation, when the door control receiver receives an unlock signal from the door
unlock detection SW, the turn signal light is flashed twice.
5. Panic Mode Function
When the panic SW on the transmitter is pressed, the door control receiver receives a signal and enters the panic mode.
The signal input into the theft deterrent ECU from the body ECU turns on the theft deterrent horn, and flashes the taillight
and headlight. When the panic SW or the unlock SW of the transmitter is pressed during the panic mode, the panic mode is
canceled, and the theft deterrent horn stops, and the taillight and headlight are turned off.
6. Repeat Function
If the lock detection signal in response to the output signal is not received after the door control receiver has output the lock
signal, the lock signal is output again.
D27 Door Control Receiver
5-Ground : Always approx. 12 volts
1-Ground : Always continuity
D21, D22, D23, D24 Door Unlock Detection SW Front LH, RH, Rear LH, RH
1-Ground : Always continuity
B4 Back Door Unlock Detection SW
1-Ground : Always continuity
System Outline
Service Hints

2004 LAND CRUISER (EWD548U)
362Air Conditioning (Front)
1. Heater Blower Operation
Manual operation
When the blower speed is set ant any speed by the blower control SW, the A/C control assembly sends a signal to the
blower motor controller, and controls the blower motor speed.
Auto operation
When the auto SW is operated, the A/C control assembly sends signals to the blower motor controller, according to the
signals from respective sensors, commands from the temperature SW etc., and controls the blower motor automatically.
2. Air Inlet Control Servo Motor Control
When the FRESH/RECIRC select SW is switched to RECIRC, the motor in the air inlet control servo motor rotates to move
the damper to the RECIRC side. The damper position is recognized by the A/C control assembly TERMINAL TPI, and
rotates the motor until the damper reaches its position.
When the FRESH/RECIRC select SW is switched to FRESH, the motor in the air inlet control servo motor rotates to move
the damper to the FRESH side. The damper position is recognized by the A/C control assembly TERMINAL TPI, and rotates
the motor until the damper reaches its position.
When the FRESH/RECIRC select SW is set to auto, the exhaust gas sensor in the engine room detects the ingredient of the
exhaust emission, and switches the FRESH/RECIRC mode automatically.
3. Air Vent Mode Control Servo Motor
When the mode select SW in the A/C control assembly is pushed, a signal is sent from the A/C control assembly, and
activates the air vent mode control servo motor. This causes the servo motor to rotate to the position selected using the
mode select SW (FACE, BI-LEVEL, FOOT, FOOT/DEF, DEF), and moves the damper.
4. Air Mix Control Servo Motor
When the temperature control SW in the A/C control assembly is pushed, a signal is sent from the A/C control assembly, and
activates the air mix control servo motor. The motor and damper is moved until it reaches the temperature set by the
temperature control SW.
5. Air Conditioning Operation
The A/C control assembly receives various signals, i. e., the engine RPM from the crankshaft position sensor, outlet
temperature from the A/C ambient temp. sensor, coolant temperature from the engine coolant temp. sensor, and the lock
signal from the A/C compressor, etc. When the engine is started and the A/C SW is turned on, a signal is sent to the A/C
control assembly. As a result, the magnetic clutch is turned on and operates the compressor.
In addition, when the engine control module detects that the magnetic clutch is on and the A/C compressor is operating, it
controls the engine in the direction to avoid lowering the engine RPM during A/C operation.
When any of the following signals are sent to the A/C control assembly, the A/C is turned off.
*Coolant temp. is high.
*Outlet air temp. is low.
*Large difference between the engine speed and compressor speed.
*The refrigerant pressure is abnormally high or low.
A45 (A), A47 (C) A/C Control Assembly
(C)11-Ground : Always approx. 12 volts
(C)22-Ground : Approx. 12 volts with ignition SW at ON or ST position
(A)27-Ground : Approx. 12 volts with ignition SW at ON or ST position (w/o navigation system)
(C) 12, (C) 14, (C) 15, (C) 17, (C) 18-Ground : Always continuity
C28 Center Cluster Integration Panel (w/ Navigation System)
2-Ground : Approx. 12 volts with ignition SW at ON or ST position
16-Ground : Always continuity
System Outline
Service Hints

2004 LAND CRUISER (EWD548U)
373
1. Cooler and Heater Blower Operation
*Manual operation
When the blower control SW in the rear A/C control SW is set to any blower speed, a signal is sent to the A/C amplifier.
The A/C amplifier controls the power transistor and operates the rear cooler blower motor and rear heater blower motor at
the set speed.
*Auto operation
When the auto SW in the rear A/C control SW is operated, a signal is sent to the A/C amplifier. The A/C amplifier controls
the power transistor according to the signals from respective sensors, and operates the rear cooler blower motor and rear
heater blower motor.
2. Air Mix Control Servo Motor Control
When the temperature control lever in the rear A/C control SW is operated, a signal is sent to the A/C amplifier. The A/C
amplifier controls the rear air mix control servo motor to operate the damper until it reaches the temperature set by the
temperature control lever.
3. Air Conditioning Operation
The cooler and heater operation can be switched by the mode select SW in the rear A/C control SW.
A32 A/C Amplifier (Rear)
1-Ground : Always approx. 12 volts
2-Ground : Approx. 12 volts with ignition SW at ON or ST position
22-Ground : Always continuity
: Parts Location
CodeSee PageCodeSee PageCodeSee Page
A32A72J1171R1673
A33B72J2272R1773
A34C72J23B72R2173
A45A70J25A72R2273
A46B70R873R2573
A47C70R973R2673
F1668R1473R3473
I1870R1573
:Junction Block and Wire Harness Connector
CodeSee PageJunction Block and Wire Harness (Connector Location)
1B24Engine Room No.2 Wire and Engine Room J/B (Engine Compartment Left)
2B28Engine Room No 2 Wire and Cowl Side J/B LH (Left Kick Panel)2C28Engine Room No.2 Wire and Cowl Side J/B LH (Left Kick Panel)
2D28Dash Wire and Cowl Side J/B LH (Left Kick Panel)2E28Dash Wire and Cowl Side J/B LH (Left Kick Panel)
2Q30Instrument Panel Integration Wire and Cowl Side J/B LH (Left Kick Panel)
3B40Engine Room No.2 Wire and Cowl Side J/B RH (Right Kick Panel)
3K40Floor No.2 Wire and Cowl Side J/B RH (Right Kick Panel)
3Q42Instrument Panel Integration Wire and Cowl Side J/B RH (Right Kick Panel)
4A
4C52Dash Wire and J/B No.4 (Instrument Panel Center)
4F
()
System Outline
Service Hints

DTC No.
Indicates the diagnostic trouble code.

Page or Instructions
Indicates the page where the inspection procedure
for each circuit is to be found, or gives instructions
for checking and repairs.

Detection Item
Indicates the system of the problem or
contents of the problem.
Trouble Area
Indicates the suspect area of the
problem.
Mass Air Flow Circuit MalfunctionDetection Item

Open or short in mass air flow meter circuit

Mass air flow meter

ECM DTC No.
(See page)Trouble AreaMIL* MemoryP0100
(DI-24)
P0101
(DI-28)
P0115
(DI-33)
Open or short in intake air temp. sensor
circuit

Intake air temp. sensor

ECM Intake Air Temp. Circuit
Malfunction P0110
(DI-29)

Open or short in engine coolant temp. sensor circuit

Engine coolant temp. sensor

ECM
P0120
Throttle/ Pedal Position Sensor/Switch
ºAº Circuit MalfunctionEngine Coolant Temp.
Circuit Malfunction

Open or short in throttle position sensor circuit

Throttle position sensor

ECM
DTC CHART (SAE Controlled)
HINT:
Parameters listed in the chart may not be exactly the same as your reading due to the type of instrument or other
factors.
If a malfunction code is displayed during the DTC check mode, check the circuit for that code listed in the table
below. For details of each code, turn to the page referred to under the ºSee pageº for the respective ºDTC No.º
in the DTC chart.
Mass Air Flow Circuit
Range/ Performance Problem
Mass air flow meter

Throttle position sensor Throttle/ Pedal Position Sensor/ Switch
ºAº Circuit Range / Performance Prob-
lem P0116
(DI-37)Engine Coolant Temp.
Circuit Range/ Performance Problem
Engine coolant temp. sensor

Cooling system
IN-32- INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
32 Author
: Date
:
2004 LAND CRUISER (RM1071U)
4. DIAGNOSTIC TROUBLE CODE CHART
The inspection procedure is shown in the table below. This table permits efficient and accurate troubleshoot-
ing using the diagnostic trouble codes displayed in the diagnostic trouble code check. Proceed with trouble-
shooting in accordance with the inspection procedure given in the diagnostic chart corresponding to the
diagnostic trouble codes displayed. The engine diagnostic trouble code chart is shown below as an example.