Page 1289 of 2572

I30331SG-4 (-)
TPO (+)
A/C Amplifier Connector
Wire Harness View:
A11
- DIAGNOSTICSAIR CONDITIONING SYSTEM
05-1 157
1347 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
HINT:
In case of using the hand-held tester, start the inspection step 1 and in case of not using the hand-held
tester, start from step 2.
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.
A C:
ItemMeasurement Item/Display
(Range)Normal ConditionDiagnostic Note
A/O DAMP POSAir outlet damper position
/min.:-14% max.:113.5%Changes depending on air outlet
power position-
A/O DAMP TARGAir outlet damper target position
/min.:-14% max.:113.5%Changes depending on air outlet
power position-
Result:
NGA
OK (Checking from the DTC)B
OK (Checking from the PROBLEM SYMPTOM TABLE)C
B REPLACE AIRCONDITIONER AMPLIFIER ASSY
C PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN IN PROBLEM SYMPTOMS TABLE (SEE
PAGE 05-1 129)
A
2 INSPECT AIRCONDITIONER AMPLIFIER ASSY(TPO, SG-4)
(a) Remove the A/C amplifier assy with connectors still con-
nected.
(b) Turn the ignition switch to the ON position.
(c) Measure the voltage according to the value(s) in the table
below.
Standard:
Tester connectionConditionSpecified condition
A11-6 (TPO) -
A11-1 (SG-4)FACE3.5 to 4.5 V
A11-6 (TPO) -
A11-1 (SG-4)DEF0.5 to 1.5 V
HINT:
As the air outlet servomotor is moved from FACE side to DEF
side, the voltage decreases gradually without interruption.
OK REPLACE AIRCONDITIONER AMPLIFIER ASSY
NG
Page 1290 of 2572
I30157
Mode Damper Servo Sub-assy
Connector Wire Harness View:
A15
I30333
FACE
DEF
I30161
3.4 -6.2
0.8 - 1.6
FACE
DEFArm Position Resistance (kW)
05-1 158
- DIAGNOSTICSAIR CONDITIONING SYSTEM
1348 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 INSPECT MODE DAMPER SERVO SUB-ASSY
(a) Remove the mode damper servo sub-assy.
(b) Measure resistance between terminals 1 and 2 of mode
damper servo sub-assy connector.
Standard:
Tester connectionConditionSpecified condition
A15-1 - A15-2Always4.2 to 7.8 kW
(c) While operating mode damper servo sub-assy as in the
procedure on page 05-1 164, measure resistance be-
tween terminals 1 and 3 of mode damper servo sub-assy.
Standard:
Tester connectionConditionSpecified condition
A15-1 - A15-3DEF3.4 to 6.2 kW
A15-1 - A15-3FACE0.8 to 1.6 kW
HINT:
As the mode damper servo sub-assy moves from DEF side to
FACE side, the resistance decreases gradually without inter-
ruption.
NG REPLACE MODE DAMPER SERVO SUB-ASSY
OK
Page 1291 of 2572
I41014
A15
S5-4 A/C Amplifier Connector
Wire Harness View:
A11
Mode Damper Servo Sub- assy
Wire Harness View:
SG-4
TPO
- DIAGNOSTICSAIR CONDITIONING SYSTEM
05-1 159
1349 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
4 CHECK HARNESS AND CONNECTOR(MODE DAMPER SERVO SUB-ASSY - A/C
AMPIFIER ASSY)
(a) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester connectionConditionSpecified condition
A11-1 (SG-4) - A15-1AlwaysBelow 1 W
A11-9 (S5-4) - A15-2AlwaysBelow 1 W
A11-6 (TPO) - A15-3AlwaysBelow 1 W
A11-1 (SG-4) -
Body groundAlways10 kW or higher
A11-9 (S5-4) -
Body groundAlways10 kW or higher
A11-6 (TPO) -
Body groundAlways10 kW or higher
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
REPLACE AIRCONDITIONER AMPLIFIER ASSY
Page 1292 of 2572

I30342
1
S5-1 SG-1
TP 12
3 2
A11
AMH
AMC 4 5A/C Amplifier Assy
A11
A11
A11 A1111
10
14
13 P
O
SB
B 3
4
5
1
2
IJ1IJ1IJ1 IJ1
IJ1 LG-R
P-L
GR Y Y-GO A14 Air Mix Damper Servo Sub-assy 05-1 160
- DIAGNOSTICSAIR CONDITIONING SYSTEM
1350 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC B1441/41 AIR MIX DAMPER CONTROL SERVOMOTOR
CIRCUIT (PASSENGER SIDE)
CIRCUIT DESCRIPTION
This air mix damper servo sub-assy is controlled by the A/C amplifier assy and moves the air mix damper
servo sub-assy to the desired position.
DTC No.Detection ItemTrouble Area
Air mix damper servo sub-assy
B1441/41Air mix damper position sensor value does not change even if
Air mix damper servo sub-assy
Harness or connector between air mix damper servo sub-B1441/41Air mix dam er osition sensor value does not change even if
A/C amplifier assy operates air mix damper servo sub-assy.
Harness or connector between air mix dam er servo sub-
assy and A/C amplifier assyA/C am lifier assy o erates air mix dam er servo sub assy.assy and A/C am lifier assy
A/C amplifier assy
WIRING DIAGRAM
05IU0-01
Page 1293 of 2572
- DIAGNOSTICSAIR CONDITIONING SYSTEM
05-1 161
1351 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
1 PERFORM ACTUATOR CHECK
(a) Set to actuator check mode (see page 05-1 117).
(b) Press the DEF switch and change to step operation.
(c) Check the air flow temperature by hand.
Display CodeAir Mix Damper Operation
0COOL side (-5 % open)
1COOL side (-5 % open)
2COOL side (-5 % open)
3COOL side (-5 % open)
4COOL/WARM (50 % open)
5COOL/WARM (50 % open)
6WARM side (105 % open)
7WARM side (105 % open)
8WARM side (105 % open)
9WARM side (105 % open)
OK:
Air flow temperature changes in accordance with
each display code.
Result:
NGA
OK
(Checking from the PROBLEM SYMPTOMS TABLE)B
OK (Checking from the DTC)C
B PROCEED TO NEXT CIRCUIT INSPECTION
SHOWN IN PROBLEM SYMPTOMS TABLE (SEE
PAGE 05-1 129)
C REPLACE AIRCONDITIONER AMPLIFIER ASSY
A
Page 1294 of 2572
I30157
Air Mix Damper Servo Sub-assy
Connector Wire Harness View:
A14
I30334
To ºWARMº
To ºCOOLº
05-1 162
- DIAGNOSTICSAIR CONDITIONING SYSTEM
1352 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
2 INSPECT AIRMIX DAMPER SERVO SUB-ASSY
(a) Remove the air mix damper servo sub-assy.
(b) Connect the positive (+) lead from the battery to terminal
4 and negative (-) lead to terminal 5, then check that the
lever turns to ºCOOLº side smoothly.
(c) Connect the positive (+) lead from the battery to terminal
5 and negative (-) lead to terminal 4, then check that the
lever turns to ºWARMº side smoothly.
NG REPLACE AIRMIX DAMPER SERVO SUB-ASSY
OK
Page 1295 of 2572
I41014
A14
A11
AMC
AMH A/C Amplifier Connector
Wire Harness View:
Air Mix Damper Servo Sub- assy
Connector Wire Harness View:
- DIAGNOSTICSAIR CONDITIONING SYSTEM
05-1 163
1353 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 CHECK HARNESS AND CONNECTOR(AIR MIX DAMPER SERVO SUB-ASSY - A/C
AMPLIFIER ASSY)
(a) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester connectionConditionSpecified condition
A11-13 (AMC) - A14-4AlwaysBelow 1 W
A11-14 (AMH) - A14-5AlwaysBelow 1 W
A11-13 (AMC) -
Body groundAlways10 kW or higher
A11-14 (AMH) -
Body groundAlways10 kW or higher
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
REPLACE AIRCONDITIONER AMPLIFIER ASSY
Page 1296 of 2572

I30342
A15
Mode Damper Servo Sub-assy
A/C Amplifier Assy
IL2 1
S5-4 SG-4
TPO 6 1
3 29
BRA11 B
AOD 8 R
AOF
45A11
A11
A11
A117 V
G 13
3
14
15
4 IL2
IL2
IL2
IL2 W
B
G
LG
L 05-1 164
- DIAGNOSTICSAIR CONDITIONING SYSTEM
1354 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC B1443/43 AIR OUTLET DAMPER CONTROL
SERVOMOTOR CIRCUIT
CIRCUIT DESCRIPTION
This circuit turns the servomotor and changes each mode damper position by the signals from the A/C ampli-
fier assy. When the AUTO switch is on, the A/C amplifier assy changes the mode automatically between
(FACE), (BI-LEVEL) and (FOOT) according to the temperature setting.
DTC No.Detection ItemTrouble Area
Mode damper servo sub-assy.
B1443/43
Air outlet damper position sensor value does not change even
if A/C lifi t i d d b
Mode damper servo sub-assy.
Harness or connector between mode damper servo sub-
B1443/43if A/C amplifier assy operates air mode damper servo sub-
assy
Harness or connector between mode dam er servo sub-
assy and A/C amplifier assy.assy.assy and A/C am lifier assy.
A/C amplifier assy.
WIRING DIAGRAM
05IU1-01