Page 961 of 2572

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2246 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC B1214 DOOR SYSTEM COMMUNICATION BUS
MALFUNCTION (+B SHORT)
DTC B1215 DOOR SYSTEM COMMUNICATION BUS
MALFUNCTION (GND SHORT)
CIRCUIT DESCRIPTION
B1214 and B1215 will be output when +B and body ground is short-circuited on the communication bus.
Detecting this condition will make all the BEAN communication unable and output some DTCs.
DTC No.DTC Detecting ConditionTrouble Area
B1214Communication circuit and +B battery system short
Power window regulator master switch assy (door ECU)
ECM
Air conditioner amplifier assy (A/C ECU)
Combination meter assy (meter ECU)
Theft warning ECU assy (theft deterrent ECU)
Sliding roof drive gear sub-assy (sliding roof ECU)
Wire harness
Multiplex network body ECU
B1215Communication circuit and body ground short
Power window regulator master switch assy (door ECU)
ECM
Air conditioner amplifier assy (A/C ECU)
Combination meter assy (meter ECU)
Theft warning ECU assy (theft deterrent)
Sliding roof drive gear sub-assy (sliding roof ECU)
Wire harness
Multiplex network body ECU
0523Y-04
Page 962 of 2572
B78727
ECM
Passenger
Side J/BMultiplex Network Body ECU
P5
Power Window
Regulator Master
Switch Assy
(Door ECU)
Combination
Meter Assy
Air Conditioner
Amplifier Assy MPX2
B9 10
6
O
IF3
IB25
1MPX1 Y
V8
MPX1MPX2
MPX2
7IB28
54F
4A SB
RS31
Short
Connector
A113E
G
MPX+MPX-5
12 2MPX1
1
T4
Theft Warning ECU Assy
(Theft deterrent ECU) IL2
G
A1018
29
GR
3J 3H 1Y C11 C12
21 9
MPX+
MPX- SBIL2 1 GRGR
IE16
Y
10
MPX1
MPX131 VCenter J/BS20
Sub Assy
(Sliding Roof ECU) B10
W
E6
9 2 12 BR7 GR
- DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
WIRING DIAGRAM
Page 963 of 2572
B61052
Multiplex Network Body ECU
Communication Circuit
Communication Circuit
Communication Circuit Communication Circuit
A ECU B ECU C ECU
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2248 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
1 CHECK DIAGNOSTIC TROUBLE CODE (A ECU)
(a) Check whether the output of the DTC will stop when the A ECU connector is disconnected.
NOTICE:
Disconnect the connectors in the operational sequence, and start the next operation after the con-
nector is connected.
HINT:
In this case, the A ECU represents the power window regulator master switch assy (door ECU).
Standard: The disconnected A ECU is abnormal when the output of the DTC stops.
OK REPLACE A ECU
NG
Page 964 of 2572
B61053
Multiplex Network Body ECU
Communication Circuit
Communication CircuitCommunication Circuit
Communication Circuit
A ECU B ECU C ECU
- DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
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2249 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
2 CHECK DIAGNOSTIC TROUBLE CODE (B ECU)
(a) Check whether the output of the DTC will stop when the B ECU connector is disconnected.
NOTICE:
Disconnect the connectors in the operational sequence, and start the next operation after the con-
nector is connected.
HINT:
In this case, the B ECU represents the sliding roof drive gear sub-assy (sliding roof ECU), combination meter
assy (meter ECU), air conditioner amplifier assy (A/C ECU) or theft warning ECU assy (theft deterrent).
Standard: The disconnected B ECU or the wire harness between the A ECU and B ECU is abnor-
mal when the output of the DTC stops.
NG Go to step 4
OK
Page 965 of 2572
B61054
Multiplex Network Body ECU
Communication Circuit
Communication Circuit
Communication CircuitCommunication Circuit
A ECU B ECU C ECU
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 CHECK WIRE HARNESS BETWEEN A ECU AND B ECU
(a) Inspect short-circuit in +B or body ground.
(1) Check whether the DTC will be output when the A ECU connector is connected.
NOTICE:
Disconnect the connectors in the operational sequence, and start the next operation after the con-
nector is connected.
OK REPLACE B ECU
NG REPAIR OR REPLACE WIRE HARNESS
BETWEEN A ECU AND B ECU
Page 966 of 2572
B60307
Multiplex Network Body ECU
Communication Circuit
Communication Circuit
Communication CircuitCommunication Circuit
A ECU B ECU C ECU
- DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
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2251 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
4 CHECK DIAGNOSTIC TROUBLE CODE (C ECU)
(a) Check whether the output of the DTC will stop when the A ECU connector is connected and the C ECU
connector is disconnected.
NOTICE:
Disconnect the connectors in the operational sequence, and start the next operation when the con-
nector is connected.
HINT:
In this case, the C ECU represents the ECM.
Standard: The disconnected C ECU or the wire harness between the B ECU and C ECU is abnor-
mal when the output of the DTC stops.
NG Go to step 6
OK
Page 967 of 2572
B60306
Multiplex Network Body ECU
Communication Circuit
Communication Circuit
Communication CircuitCommunication Circuit
A ECU B ECU C ECU
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
5 CHECK WIRE HARNESS BETWEEN B ECU AND C ECU
(a) Inspect short-circuit in +B or body ground.
(1) Check whether the DTC will be output when the B ECU connector is connected.
NOTICE:
Disconnect the connectors in the operational sequence, and start the next operation after the con-
nector is connected.
OK REPLACE C ECU
NG REPAIR OR REPLACE WIRE HARNESS
BETWEEN B ECU AND C ECU
Page 968 of 2572

B60308
Multiplex Network Body ECU
Communication Circuit
Communication Circuit
Communication Circuit Communication Circuit
A ECU B ECU C ECU
- DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
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2253 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
6 CHECK WIRE HARNESS MPX BODY ECU AND A ECU OR C ECU
(a) Inspect short-circuit in +B or body ground.
(1) Disconnect the connectors of the A ECU and multiplex network body ECU.
(2) Inspect short-circuit in +B of the wire harness between the A ECU and multiplex network body
ECU, and also in the body ground.
Standard:
0 V when short-circuited in +B.
No continuity between each ECU terminal and the body ground when short-circuited in the
body ground.
HINT:
In this case, the A ECU represents the power window regulator master switch assy (door ECU).
(3) Inspect short-circuit in +B of the wire harness between the C ECU and multiplex network body
ECU, and also in the body ground.
Standard:
0 V when short-circuited in +B.
No continuity between each ECU terminal and the body ground when short-circuited in the
body ground.
HINT:
In this case, the C ECU represents the ECM.
NG REPAIR OR REPLACE WIRE HARNESS
BETWEEN MPX BODY ECU AND A ECU OR C
ECU
OK
REPLACE MULTIPLEX NETWORK BODY ECU