TOYOTA HIGHLANDER 2001 Service Repair Manual
Page 1481 of 2572
- DIAGNOSTICSAIR CONDITIONING SYSTEM
05-1 191
1381 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
1 READ VALUE OF HAND-HELD TESTER
(a) Connect the hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand-held tester main switch ON.
(c) Select the items below in the DATA LIST, and read the displays on the hand-held tester.
ENGINE AND ECT / ALL:
ItemMeasurement Item/Display
(Range)Normal ConditionDiagnostic Note
A/C SIGA/C signal/ ON or OFFA/C ON: ON-
A/C MAG CLUTCHA/C magnet clutch/ ON or OFFA/C magnet clutch ON: ON-
NG INSPECT MULTIPLEX COMMUNICATION
CIRCUIT
OK
2 PERFORM ACTIVE TEST USING HAND-HELD TESTER
(a) Connect the hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand-held tester main switch ON.
(c) Select the item below in the ACTIVE TEST, and then check that the relay operates.
ENGINE AND ECT / ALL:
ItemTest Details/Display (Range)Diagnostic Note
A/C MAG CLUTCHMagnetic clutch relay / OFF, ONOperating sound can be heard
NG Go to step 3
OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (SEE PAGE
05-1 129)
Page 1482 of 2572
Z18060
5
13
2
23
15
le32E05280
Magnet Clutch Assy Connector
From View:
A2
I36159
ECM Connector Wire Harness View:
E6
05-1 192
- DIAGNOSTICSAIR CONDITIONING SYSTEM
1382 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 INSPECT MAGNET-CLUTCH RELAY
(a) Remove the relay (magnet clutch relay) from the engine
room R/B.
(b) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester connectionConditionSpecified condition
3 - 5Always10 kW or higher
3 - 5When battery voltage ap-
plied to terminals 1 and 2Below 1 W
NG REPLACE MAGNET-CLUTCH RELAY
OK
4 INSPECT MAGNET CLUTCH ASSY
(a) Disconnect the connector from the magnet clutch assy.
(b) Connect the positive (+) lead from the battery to terminal
3 and negative (-) lead to body ground, then check that
the magnet clutch assy is engaged.
NG REPLACE MAGNET CLUTCH ASSY
OK
5 INSPECT ECM
(a) Remove the ECM and disconnect the connector.
(b) Measure the voltage according to the value(s) in the table
below.
Standard:
Tester connectionConditionSpecified condition
E6-2 (ACMG) - Body
groundIgnition switch ON10 to 14 V
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
Page 1483 of 2572
I36159E51630I38853
A2
Magnet Clutch Assy Connector
Wire Harness View:ECM Connector
Wire Harness View:
E6
ACMG
- DIAGNOSTICSAIR CONDITIONING SYSTEM
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1383 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
6 CHECK HARNESS AND CONNECTOR
(a) Disconnect the connector.
(b) Measure the voltage according to the value(s) in the table
below.
Standard:
Tester connectionConditionSpecified condition
A2-3 - Body ground
Ignition switch ON
When using service wire,
terminal E6-2 (ACMG)
and Body ground are not
connect
Below 1 V
A2-3 - Body ground
Ignition switch ON
When using service wire,
terminal E6-2 (ACMG)
and Body ground are con-
nect
10 to 14 V
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
REPLACE ECM
Page 1484 of 2572
Duty Ratio =A + BA
x 100 (%)
ON
OFFA
B
1 cycle
Blower Level
0
Si duty (%)
LO M1 M2HI
2941
6789
53 M3
I30519
IL2 1
W
IH1BLW A1017
LGA/C Amplifier Assy
B7
Blower Motor Control
5
P-L
2
1 4
3SI
GND VM
+B 1
2
R
B B
B 2
B
IH1W-B
IH1 3
W-B
IA From
H9
Heater
RelayB6
Blower Motor
- DIAGNOSTICSAIR CONDITIONING SYSTEM
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
BLOWER MOTOR CIRCUIT
CIRCUIT DESCRIPTION
The blower motor is operated by signals from the A/C amplifier
assy. Blower motor speed signals are transmitted by changes
in the Duty Ratio.
Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle.
For example, if A is the period of continuity in one cycle, B is the
period of non-continuity.
WIRING DIAGRAM
05IU6-01
Page 1485 of 2572
I41004
B7
A10
SI
A/C Amplifier Connector
Wire Harness View: Blower Motor Controller Connector
Front View:
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
1 PERFORM ACTUATOR CHECK
(a) Set the actuator check mode (see page 05-1 117).
(b) Press the blower switch to change to the step operation.
(c) Check the air flow level by hand.
Display CodeBlower level
00
11
214
314
414
514
614
714
814
931
OK:
Blower level changes in accordance with each display code.
NG Go to step 2
OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (SEE PAGE
05-1 129)
2 CHECK HARNESS AND CONNECTOR(BLOWER MOTOR CONTROLLER - A/C
AMPLIFIER)
(a) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester connectionConditionSpecified condition
A10-17 (BLW) -
B7-2 (SI)AlwaysBelow 1 W
A10-17 (BLW) -
Body groundAlways10 kW or higher
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
Page 1486 of 2572
E69146
B7
GND
Blower Motor Controller Connector
Front View:
E68546E69147
+- Blower w/ Fan Motor Sub-assy
Front View:
B6
- DIAGNOSTICSAIR CONDITIONING SYSTEM
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 CHECK HARNESS AND CONNECTOR(BLOWER MOTOR CONTROLLER - BODY
GROUND)
(a) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester connectionConditionSpecified condition
B7-1 (GND) -
Body groundAlwaysBelow 1 W
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
4 INSPECT COOLING UNIT MOTOR SUB-ASSY W/FAN
(a) Remove the blower w/ fan motor sub-assy.
(b) Connect positive (+) lead to terminal 2 of the blower motor
connector and negative (-) lead to terminal 1.
Standard: Blower motor operates smoothly.
NG REPLACE COOLING UNIT MOTOR SUB-ASSY
W/FAN
OK
Page 1487 of 2572
I41008
Wire to wire A/C Sub No.2 Wire Connector
Front View:
IH1
B7
B6
A/C Sub No.2 Wire Connector
Front View:
A/C Sub No.2 Wire Connector
Front View:
+B
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
5 CHECK A/C SUB NO.2 WIRE
(a) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester connectionConditionSpecified condition
IH1-2 - B6-2AlwaysBelow 1 W
IH1-2 - B7-3 (+B)AlwaysBelow 1 W
B6-2 - B7-3 (+B)AlwaysBelow 1 W
NG REPAIR OR REPLACE A/C SUB NO.2 WIRE
OK
Page 1488 of 2572
I36240
B7
B6
VM
Blower Motor Connector Front View: Blower Motor Controller Connector
Front View:
- DIAGNOSTICSAIR CONDITIONING SYSTEM
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
6 CHECK HARNESS AND CONNECTOR(BLOWER MOTOR CONTROLLER -
BLOWER MOTOR)
(a) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester connectionConditionSpecified condition
B7-4 (VM) - B6-1AlwaysBelow 1 W
B7-4 (VM) -
Body groundAlways10 kW or higher
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
Page 1489 of 2572
I38764
A10
BLW
A/C Amplifier
Connector
Wire Harness View:
I31456
GND 2V/
Division
500m sec./ Division
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
7 INSPECT AIR CONDITIONING AMPLIFIER(BLW - BODY GROUND)
(a) Remove the A/C amplifier with the connectors still con-
nected.
(b) Turn the ignition switch to the ON position.
(c) Turn the blower switch on (Lo).
(d) Measure the waveform between terminal BLW (A10-17)
of the A/C amplifier and body ground.
OK:
Waveform operates as shown in the illustration.
HINT:
Waveform varies with the blower level.
NG REPLACE AIR CONDITIONING AMPLIFIER
OK
REPLACE BLOWER MOTOR CONTROL
Page 1490 of 2572
I30344
A/C Amplifier Assy A13
Recirculation Damper Servo Sub-assy
(Air Inlet Control Servo Motor)
Y
W
B4
6
5 5
2
1A10
A10
A10MR/F
AIF
AIR
- DIAGNOSTICSAIR CONDITIONING SYSTEM
05-1 177
1367 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
RECIRCULATION DAMPER SERVOMOTOR CIRCUIT
CIRCUIT DESCRIPTION
The A/C amplifier assy controls the recirculation damper servo sub-assy and moves it to the desired posi-
tion.
WIRING DIAGRAM
05IU5-02