Ecu ground TOYOTA HIGHLANDER 2001 Service Repair Manual

'05 HIGHLANDER_U (L/O 0409)
325
2005 HIGHLANDER from Nov. '04 Prod. (OM48570U)
Never load the trailer with more
weight in the back than in the
front. About 60% of the trailer load
should be in the front half of the
trailer and the remaining 40% in the
rear.
HITCHES

If you wish to install a trailer hitch, you
should consult with your Toyota dealer.

Use only a hitch recommended by the
hitch manufacturer and the one which
conforms to the total trailer weight
requirement.

The hitch must be bolted securely to
the vehicle frame and installed accord-
ing to the hitch manufacturer 's instruc-
tions.

The hitch ball and king pin should have
a light coat of grease.

Toyota recommends removing the trail-
er hitch whenever you are not towing
a trailer to reduce the possibility of
additional damage caused by the hitch
if your vehicle is struck from behind.
After removing the hitch, seal any
mounting holes in the vehicle body to
prevent entry of pollutants such as ex-
haust fumes, dirt, water, etc.
NOTICE
Do not use axle- mounted hitches as
they can cause damage to the axle
housing, wheel bearings, wheels or
tires.
BRAKES AND SAFETY CHAINS

Toyota recommends trailers with
brakes that conform to any applica-
ble federal and state/provincial regu-
lations.

A safety chain must always be used
between the towing vehicle and the
trailer. Leave sufficient slack in the
chain for turns. The chain should
cross under the trailer tongue to
prevent the tongue from dropping to
the ground in case it becomes dam-
aged or separated. For correct safety
chain procedures, follow the hitch or
trailer manufacturer 's recommenda-
tions.
CAUTION

If the total trailer weight exceeds
453 kg (1000 lb.), trailer brakes are
required.

Never tap into your vehicle's hy-
draulic system as it would lower its
braking effectiveness.

Never tow a trailer without using a
safety chain securely attached to
both the trailer and the vehicle. If
damage occurs to the coupling unit
or hitch ball, there is danger of the
trailer wandering over into another
lane.
TIRES

Ensure that your vehicle's tires are
properly inflated. See page 385 in Sec-
tion 7- 2 and page 410 in Section 8 for
instructions.

The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.

2005 HIGHLANDER (EWD592U)
107
Previous automatic transaxle 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
During driving the engine warm up condition signal is input from engine coolant temp. sensor to TERMINAL THW of the
engine control module, and the vehicle speed signal is input from the ABS speed sensor to skid control ECU, and are sent to
the engine control module through communication control. At the same time, the throttle valve opening signal is sent from
the throttle position sensor to the TERMINALS VTA1 and VTA2 of the engine control module, as the throttle angle signal.
2. Lock-Up Operation
When the engine control module decides based on each signal that the lock-up condition has been met, the current flows
through TERMINAL DSL of the engine control module to TERMINAL 10 of the electronically controlled transmission solenoid
to GROUND.
3. 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.
4. Overdrive Circuit
*O/D main SW on
When the O/D main SW is turned on, a signal is input to TERMINAL ODMS of the engine control module and engine
control module operation causes gear shift when the conditions for overdrive are met.
*O/D main SW off
When the O/D main SW is turned off, a signal is input into TERMINAL ODMS of the engine control module, and turns on
the O/D off indicator light. This activates the ECU, and the transmission system is controlled not to shift to overdrive.
E4 Electronically Controlled Transmission Pattern Select SW
3-4 : Closed with the select SW at SNOW position
E5 (A), E6 (B), E7 (E), E8 (D), E9 (C) Engine Control Module
BATT-E1 : Always approx. 12 volts
MREL-E1 : Approx. 12 volts with the ignition SW ON position
P1 A/T Indicator SW
2-6 : Closed with the shift lever in P position
2-1 : Closed with the shift lever in R position
2-9 : Closed with the shift lever in N position
2-7 : Closed with the shift lever in D position
2-3 : Closed with the shift lever in 2 position
2-8 : Closed with the shift lever in L position
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A10A42E5A42P544
A11B42E6B42S1543
A1742E7E42S2739 (3MZ-FE)
B9A42E8D42S28A43
B10B42E9C42S29B43
C638 (3MZ-FE)G543S30A43
C11A42J239 (3MZ-FE)S31B43
C12B42J643T339 (3MZ-FE)
E138 (3MZ-FE)J743T1339 (3MZ-FE)
E238 (3MZ-FE)J1743T1643
E442P139 (3MZ-FE)
System Outline
Service Hints

2005 HIGHLANDER (EWD592U)
11 5
Previous automatic transaxle 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
During driving the engine warm up condition signal is input from engine coolant temp. sensor to TERMINAL THW of the
engine control module, and the vehicle speed signal is input from the ABS speed sensor to skid control ECU, and are sent to
the engine control module through communication control. At the same time, the throttle valve opening signal is sent from
the throttle position sensor to the TERMINALS VTA1 and VTA2 of the engine control module, as the throttle angle signal.
2. Lock-Up Operation
When the engine control module decides based on each signal that the lock-up condition has been met, the current flows
through TERMINAL DSL of the engine control module to TERMINAL 3 of the electronically controlled transmission solenoid
to GROUND.
3. 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.
4. Overdrive Circuit
*O/D main SW on
When the O/D main SW is turned on, a signal is input to TERMINAL ODMS of the engine control module and engine
control module operation causes gear shift when the conditions for overdrive are met.
*O/D main SW off
When the O/D main SW is turned off, a signal is input into TERMINAL ODMS of the engine control module, and turns on
the O/D off indicator light. This activates the ECU, and the transmission system is controlled not to shift to overdrive.
E4 Electronically Controlled Transmission Pattern Select SW
3-4 : Closed with the select SW at SNOW position
E5 (A), E6 (B), E7 (E), E8 (D), E9 (C) Engine Control Module
BATT-E1 : Always approx. 12 volts
MREL-E1 : Approx. 12 volts with the ignition SW ON position
P1 A/T Indicator SW
2-6 : Closed with the shift lever in P position
2-1 : Closed with the shift lever in R position
2-9 : Closed with the shift lever in N position
2-7 : Closed with the shift lever in D position
2-3 : Closed with the shift lever in 2 position
2-8 : Closed with the shift lever in L position
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A10A42E6B42S1543
A11B42E7E42S2741 (2AZ-FE)
A1742E8D42S28A43
B9A42E9C42S29B43
B10B42E1040 (2AZ-FE)S30A43
C640 (2AZ-FE)G543S31B43
C11A42J241 (2AZ-FE)T341 (2AZ-FE)
C12B42J643T1341 (2AZ-FE)
E240 (2AZ-FE)J743T1643
E442P141 (2AZ-FE)
E5A42P544
System Outline
Service Hints

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120
Headlight with Daytime Running Light
1. Daytime Running Light Operation
The headlight is turned on when all the following conditions are satisfied
*When the ignition switch is ON position
*When the generator is generating electricity
*When the light control SW is OFF position
*When the parking brake SW is OFF position
2. Headlight Operation
*The headlight comes on at the LOW position when the dimmer SW is turned to the low beam position with the light control
SW being HEAD position.
*If the dimmer SW is turned to the HIGH position with the light control SW being HEAD position, the headlight comes on at
the high beam position. Moreover, the high beam indicator light appears on the combination meter.
*Regardless of the light control SW positions, the headlight comes on at the low beam position when the dimmer SW is
turned to FLASH position. Moreover, the high beam indicator light appears on the combination meter.
B9 (A), B10 (B), B12 (D) Body ECU
(D) 7-Ground : Always continuity
(D)14-Ground : Continuity with parking brake pedal depressed
(B)17-Ground : Continuity with the light control SW at HEAD position
(A) 2-Ground : Always continuity
(A) 5-Ground : Approx. 12 volts with the ignition SW at ON position
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
B9A42H138 (3MZ-FE)H440 (2AZ-FE)
B10B42H140 (2AZ-FE)J139 (3MZ-FE)
B11C42H238 (3MZ-FE)J141 (2AZ-FE)
B12D42H240 (2AZ-FE)J339 (3MZ-FE)
C11A42H338 (3MZ-FE)J341 (2AZ-FE)
C12B42H340 (2AZ-FE)M343
C1342H438 (3MZ-FE)P343
: RELAY BLOCKS
CodeSee PageRelay Blocks (Relay Block Location)
222Engine Room R/B (Engine Compartment Left)
323Engine Room R/B No.3 (Engine Compartment Rear Left)
System Outline
Service Hints

2005 HIGHLANDER (EWD592U)
139
Illuminated Entry System
This system provides various functions listed below through communication control of the body ECU etc.
*Each relevant light lights up if any door is opened.
*If all the doors are closed with the ignition SW set at OFF after any door is opened, each light lights up for 15 sec., and
then fades out when the time set on the timer has elapsed.
*If any door is unlocked from the driver or passenger side or if any door is unlocked with the unlock SW on the transmitter
after all the doors are closed and locked, each light lights up for 15 sec., and then fades out when the time set on the timer
has elapsed.
*If the ignition SW is turned to the ACC or ON position while each light is being lit by the timer, the timer lighting is cancelled
and the light fades out.
*If all the doors are closed with the ignition SW set at ACC or ON after any door is opened, the timer lighting is cancelled
and the light fades out.
*Each light above is the interior light, ignition key cylinder light, and door courtesy lights.
D7, D8, D9, D10 Door Courtesy SW Front LH, RH, Rear LH, RH
1-Ground : Closed with the door open
R12 Rear Interior Light SW
1-2 : Closed with the back door open
B9 (A), B12 (D) Body ECU
(D) 9-Ground : Always approx. 12 volts
(A) 5-Ground : Approx. 12 volts with the ignition SW at ON position
(A)17-Ground : Approx. 12 volts with the ignition SW at ACC or ON position
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A10A42D644O544
A11B42D744P544
A1742D844R1145
B9A42D944R1245
B10B42D1044S30A43
B11C42E642S31B43
B12D42G543T743
C11A42I1443V945
C12B42I1644V1045
D444J1344
D544J1444
System Outline
Service Hints

2005 HIGHLANDER (EWD592U)
149
With the ignition SW turned on, the current flows to TERMINAL (A) 5 of the body ECU through IG1 fuse.
Voltage is applied at all times to TERMINAL (A) 7 of the body ECU through the TAILLIGHT relay. Coil side, and to
TERMINAL (C) 3 through the HEAD LAMP relay coil side (w/o daytime running light) or through the DRL NO.2 relay (w/
daytime running light).
1. Normal Lighting Operation

With the light control SW turned to TAIL position, a signal is input into TERMINAL (B) 18 of the body ECU. Due to this signal,
the current flowing to TERMINAL (A) 7 of the body ECU flows to TERMINAL (B) 18 to TERMINAL 14 of the light control SW
to TERMINAL 16 to GROUND, and TAILLIGHT relay causes taillights to turn on.

With the light control SW turned to HEAD position, a signal is input into TERMINALS (B) 17 and (B) 18 of the body ECU. Due
to this signal, the current flowing to TERMINAL (C) 3 of the body ECU flows to TERMINAL (B) 17 to TERMINAL 13 of the
light control SW to TERMINAL 16 to GROUND in the headlight circuit, and causes TAILLIGHT and HEAD LAMP (w/o
daytime running light) or DRL NO.2 relay (w/ daytime running light) to turn the lights on. The taillight circuit is same as above.
2. Light Auto Turn Off Operation
With light on and ignition SW turned off (Input signal goes to TERMINAL (A) 5 of the body ECU), when the driver's door is
opened (Input signal goes to TERMINAL (C) 11 of the body ECU), the ECU operates and the current is cut off which flows
from TERMINAL (A) 7 of the body ECU to TERMINAL (B) 18 in taillight circuit and from TERMINAL (C) 3 to TERMINAL (B)
17 in headlight circuit.
As a result, all lights are turned off automatically.
B9 (A), B10 (B), B12 (D) Body ECU
(D) 9-Ground : Always approx. 12 volts
(A) 5-Ground : Approx. 12 volts with the ignition SW at ON position
(B)17-Ground : Continuity with the light control SW at HEAD position
K4 Unlock Warning SW
2-1 : Closed with the ignition key in the cylinder
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
B9A42C1342J643
B10B42D744K443
B11C42F738 (3MZ-FE)
B12D42F740 (2AZ-FE)
: RELAY BLOCKS
CodeSee PageRelay Blocks (Relay Block Location)
323Engine Room R/B No.3 (Engine Compartment Rear Left)
System Outline
Service Hints

2005 HIGHLANDER (EWD592U)
184
VSC and Tire Pressure Warning System
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 skid control ECU with actuator 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
skid control ECU with actuator 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 front 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 mulfunction occurs in the VSC system, the VSC indicator lights up to warn the driver.
4. 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 control
The engine power does not interfere with the VSC brake control by fuel cut controlling 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 alarm intermittently to warn the driver that the current road is slippery, while the
VSC system is being operated.
5. Fail Safe Function
If an mulfunction occurs in the skid control ECU with actuator, sensor signals, and/or actuators, the skid control ECU with
actuator inhibits the brake actuator control and inputs the mulfunction signal to the engine control module. According to the
mulfunction signal, the brake actuator turns off the solenoid and the engine control module rejects any electronically
controlled request from the VSC system. As a result, the vehicle functions without the ABS, BA, TRAC, and VSC systems.
A4, A5 ABS Speed Sensor Front LH, RH
1-2 : 1.4-1.8 kW (20°C, 68°F)
A24, A25 ABS Speed Sensor Rear LH, RH
1-2 : 0.9-1.3 kW (25°C, 77°F) (4WD)
1-2 : Max. 1.45 kW (25°C, 77°F) (2WD)
B4 Brake Warning SW
1-2 : Closed with the float down
S27 Skid Control ECU with Actuator
46-Ground : Approx. 12 volts with the ignition SW at ON position
27-Ground : Approx. 12 volts with the stop light SW on (Brake pedal depressed)
31-Ground : Always continuity
S15 Stop Light SW
2-1 : Closed with brake pedal depressed
System Outline
Service Hints

2005 HIGHLANDER (EWD592U)
191
Communication between power window master SW and body ECU is controlled and body ECU recognizes the conditions of
each SW to control the operation of windows.
1. Manual Up or Down Operation (Driver's Window, Passenger's Window)
During you are pushing power window master SW (Driver side) halfway down, the motor operates and the window on the
driver's side opens. During you are pulling power window master SW (Driver side) halfway up, the motor operates and the
windows on the driver's side closes. The window on the passenger's side opens or closes by pushing down or pulling up
power window master SW (Front passenger, rear passenger) or power window SW front RH, rear LH, RH.
2. Auto Up or Down Operation (Driver's Window)
When the power window master SW (Driver side) is fully pushed down, the motor operates and the window on the driver's
side automatically opens. When the power window master SW (Driver side) is fully pulled up, the motor operates and the
window on the driver's side automatically closes.
3. Stopping Automatic Window Operation
If you push the power window master SW (Driver side) halfway down during the window on the driver's side is raising
automatically, the motor's operation stops. And if you pull the power window master SW (Driver side) halfway up during the
window on the driver's side is lowering automatically, the motor's operation stops.
4. Key Off Power Window Operation
After the ignition SW is turned off, the windows can be operated for about 43 seconds. However, the window operation stops
when either front doors opens.
5. Jam Protection Function (Driver's Window)
When any foreign object gets caught during power window UP operation, the motor rotates in the opposite direction to open
the window.
B9 (A), B12 (D) Body ECU
(D) 9-Ground : Always approx. 12 volts
(A) 2, (D) 7-Ground : Always continuity
(A) 5-Ground : Approx. 12 volts with the ignition SW at ON position
P5 Power Window Master SW with ECU
9, 10-Ground : Always approx. 12 volts
2-Ground : Always continuity
P10, P11, P12 Power Window SW Front RH, Rear LH, RH
7-Ground : Always approx. 12 volts
1-Ground : Always continuity
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A10A42C12B42P944
A11B42D1244P1044
A1742E642P1144
B9A42G543P1244
B10B42P544S30A43
B11C42P644S31B43
B12D42P744
C11A42P844
System Outline
Service Hints

2005 HIGHLANDER (EWD592U)
197
The door lock control is controlled through the various signals input into the body ECU through communication control of the
body ECU etc.
1. Manual Operation
All doors can be Locked/Unlocked through the operation of the driver and passenger side door lock control SW.
2. Double Operation Unlock Operation
When the door key lock and unlock SW front LH is turned to the unlock side, only the driver's door is unlocked. And if the
door key lock and unlock SW front LH is turned to the unlock side again within 3 seconds, all the doors to unlock.
3. Manual Unlock Protection
Once the doors are locked by the door knob (Key less operation), the door key or the transmitter, they can not be unlocked
by the door lock control SW. The protection is canceled when the ignition SW is turned on or unlock operation is made by the
door key or the transmitter.
4. Ignition Key Reminder Operation
When the door lock operation is made using the door knob with the ignition key remained inserted in the key cylinder and the
door open, unlock operation is automatically made. Additionally, if lock operation is made with the door lock control SW or
door key lock and unlock SW, unlock operation is automatically made after the lock operation has been completed.
D7, D8, D9, D10 Door Courtesy SW Front LH, RH, Rear LH, RH
1-Ground : Continuity with the door open
D12 Door Key Lock and Unlock SW,Door Lock Motor and Door Unlock Detection SW Front LH
5-Ground : Approx. 12 volts with the door lock motor at lock operate
6-Ground : Approx. 12 volts with the door lock motor at unlock operate
4-2 : Closed with the door lock cylinder locked with key
3-2 : Closed with the door lock cylinder unlocked with key
D13 Door Key Lock and Unlock SW,Door Lock Motor and Door Unlock Detection SW Front RH
1-Ground : Approx. 12 volts with the door lock motor at lock operate
2-Ground : Approx. 12 volts with the door lock motor at unlock operate
3-5 : Closed with the door lock cylinder locked with key
4-5 : Closed with the door lock cylinder unlocked with key
D14 Door Lock Motor and Door Unlock Detection SW Rear LH
1-Ground : Approx. 12 volts with the door lock motor at lock operate
2-Ground : Approx. 12 volts with the door lock motor at unlock operate
D15 Door Lock Motor and Door Unlock Detection SW Rear RH
1-Ground : Approx. 12 volts with the door lock motor at lock operate
2-Ground : Approx. 12 volts with the door lock motor at unlock operate
B15 Back Door Lock Motor and Back Door Unlock Detection SW
1-Ground : Approx. 12 volts with the door lock motor at lock operate
2-Ground : Approx. 12 volts with the door lock motor at unlock operate
System Outline
Service Hints

2005 HIGHLANDER (EWD592U)
205
D7, D8, D9, D10 Door Courtesy SW Front LH, RH, Rear LH, RH
1-Ground : Continuity with the door open
D12 Door Key Lock and Unlock SW,Door Lock Motor and Door Unlock Detection Front LH
5-Ground : Approx. 12 volts with the door lock motor at lock operate
6-Ground : Approx. 12 volts with the door lock motor at unlock operate
4-2 : Closed with the door lock cylinder locked with key
3-2 : Closed with the door lock cylinder unlocked with key
D13 Door Key Lock and Unlock SW Door Lock Motor and Door Unlock Detection Front RH
1-Ground : Approx. 12 volts with the door lock motor at lock operate
2-Ground : Approx. 12 volts with the door lock motor at unlock operate
3-5 : Closed with the door lock cylinder locked with key
4-5 : Closed with the door lock cylinder unlocked with key
D14 Door Lock Motor and Door Unlock Detection SW Rear LH
3-Ground : Approx. 12 volts with the door lock motor at lock operate
4-Ground : Approx. 12 volts with the door lock motor at unlock operate
D15 Door Lock Motor and Door Unlock Detection SW Rear RH
1-Ground : Approx. 12 volts with the door lock motor at lock operate
2-Ground : Approx. 12 volts with the door lock motor at unlock operate
B15 Back Door Lock Motor and Back Door Unlock Detection SW
1-Ground : Approx. 12 volts with the door lock motor at lock operate
2-Ground : Approx. 12 volts with the door lock motor at unlock operate
W6 Wireless Door Lock ECU
5-Ground : Always approx. 12 volts
1-Ground : Always continuity
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A10A42D1144J1643
A11B42D1244J1844
A1742D1344J1944
B9A42D1444K443
B10B42D1544O544
B11C42E642P544
B12D42G543R1245
B1544I1443S30A43
C11A42I1644S31B43
C12B42J543T443
D342J643T743
D744J1044T843
D844J1244W539 (3MZ-FE)
D944J1344W541 (2AZ-FE)
D1044J1444W645
Service Hints