Dtc B2326 Can Ms Bus Line Communication Malfunction

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK VEHICLE TYPE

CHECK CAN MS BUS WIRE

RECONFIRM DTC OUTPUT

CHECK CAN MS BUS WIRE

CHECK FOR OPEN IN CAN MS BUS WIRE (CAN MS BUS BRANCH WIRE)

REPLACE CLEARANCE WARNING ECU

CHECK DTC OUTPUT

CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (CAN NO. 3 J/C - MAIN BODY ECU)

CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

CHECK OPEN IN CAN BUS MAIN WIRE

CHECK FOR OPEN IN CAN BUS MAIN WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

CHECK FOR SHORT IN CAN MS BUS WIRES (CAN NO. 3 J/C WIRE)

CHECK FOR SHORT IN CAN MS BUS WIRES (CERTIFICATION ECU MAIN WIRE)

CHECK FOR SHORT IN CAN MS BUS WIRES (CERTIFICATION ECU - CAN NO. 3 J/C)

CHECK FOR SHORT IN CAN MS BUS WIRES (CLEARANCE WARNING ECU BRANCH WIRE)

CHECK FOR SHORT IN CAN MS BUS WIRES (CLEARANCE WARNING ECU)

CHECK FOR OPEN IN CAN BUS MAIN WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CAN NO. 3 J/C WIRE)

CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CLEARANCE WARNING ECU - CAN NO. 3 J/C)

CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CAN NO. 3 J/C WIRE)

CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CLEARANCE WARNING ECU - CAN NO. 3 J/C)

CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO . 3 J/C)

CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

CHECK CAN BUS MAIN WIRE (CERTIFICATION ECU)

CHECK CAN BUS MAIN WIRE (MAIN BODY ECU - CERTIFICATION ECU)

CHECK CAN BUS MAIN WIRE (CERTIFICATION ECU)

CHECK CAN BUS MAIN WIRE (MAIN BODY ECU - CERTIFICATION ECU)

DTC B2326 CAN MS Bus Line Communication Malfunction

DESCRIPTION

1. The main body ECU will store this DTC when no signals can be received from the ECUs that have been memorized as those that are connected to the CAN MS bus.
   
2. When the main body ECU receives a response signal from the ECUs connected to the CAN MS bus, the main body ECU recognizes and memorizes that the ECU is connected to the CAN MS bus. Based on this memorized data, the main body ECU monitors for malfunctions in the ECUs connected to the CAN MS bus when communicating with those ECUs. If the main body ECU cannot receive response signals from the ECUs that have been memorized as those connected to the CAN MS bus, the main body ECU determines that a malfunction exists.
   

DTC No.	DTC Detection Condition	Trouble Area
B2326	Main body ECU cannot receive signals from all ECUs that have been memorized as those connected to the CAN MS bus.	Open or short in MS bus main line Open or short in MS bus branch lines Certification ECU Clearance warning ECU Main body ECU No. 3 CAN J/C

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

1. Turn the ignition switch off before measuring the resistances of the CAN sub bus main wire and the CAN sub bus branch wire.
   
2. After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
   
3. Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches, or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.
   

HINT:

1. Operating the ignition switch, any switches, or a door triggers related ECU and sensor communication with the CAN. This communication will cause the resistance value to change.
   
2. Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below will help determine the cause of the malfunction.
   

1.CHECK VEHICLE TYPE

Vehicle Type	Proceed to
For vehicle w/o TOYOTA Parking assist-sensor system	A
For vehicle w/ TOYOTA Parking assist-sensor system	B

B	Go to step 4

A

2.CHECK CAN MS BUS WIRE

1. Turn the ignition switch off.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard Resistance:

   Tester Connection	Condition	Specified Value	Result
   E74-27 (CANH) - E74-28 (CANL)	Ignition switch off	54 to 69 Ω	Below 54 Ω: Short circuit between bus lines
   			70 Ω or higher: Open circuit in a main bus line
   E74-27 (CANH) - E74-17 (E)	Ignition switch off	200 Ω or higher	Below 200 Ω: CANH ground short
   E74-28 (CANL) - E74-17 (E)	Ignition switch off		Below 200 Ω: CANL ground short

3. Disconnected the cable from the negative (-) battery terminal.
   

4. Measure the resistance according to the value(s) in the table below.
   

   Standard Resistance:

   Tester Connection	Condition	Specified Value	Result
   E74-27 (CANH) - E74-1 (+B)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Below 6 kΩ: CANH +B short
   E74-28 (CANL) - E74-1 (+B)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Below 6 kΩ: CANL +B short

   Result:

   Result	Proceed to
   OK	A
   NG Open circuit in a main bus line Short circuit between bus lines	B
   NG Ground short +B short	C

B	Go to step 28
C	Go to step 30

A

3.RECONFIRM DTC OUTPUT

1. Clear DTCs.
   

2. Turn the ignition switch off.
   

3. Turn the ignition switch ON, recheck the DTC.
   

   Result:

   Result	Proceed to
   B2326 output	A
   Other DTC output	B

B	GO TO DTC CHART

A
REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)

4.CHECK CAN MS BUS WIRE

1. Turn the ignition switch off.
   

2. Measure the resistance according to the value(s) in the table below.
   

   HINT:

   O32 connector color: White

   Standard Resistance:

   Tester Connection	Condition	Specified Value	Result
   O32-1 (CANH) - O32-2 (CANL)	Ignition switch off	54 to 69 Ω	Below 54 Ω: Short circuit between bus lines
   			70 Ω or higher: Open circuit in a main bus line
   O32-1 (CANH) - E10-4 (CG)	Ignition switch off	200 Ω or higher	Below 200 Ω: CANH ground short
   O32-2 (CANL) - E10-4 (CG)	Ignition switch off		Below 200 Ω: CANL ground short

3. Disconnected the cable from the negative (-) battery terminal.
   

4. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value	Result
   O32-1 (CANH) - E10-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Below 6 kΩ: CANH +B short
   O32-2 (CANL) - E10-16 (BAT)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher	Below 6 kΩ: CANL +B short

Result:

Result	Proceed to
OK	A
NG (Open circuit in a main bus line)	B
NG (Short circuit between bus lines)	C
NG (+B short)	D
NG (Ground short)	E

B	Go to step 8
C	Go to step 12
D	Go to step 18
E	Go to step 23

A

5.CHECK FOR OPEN IN CAN MS BUS WIRE (CAN MS BUS BRANCH WIRE)

1. Check for the clearance warning ECU sub bus branch wire and power source circuit (CAMRY_ACV40 RM000002E7700RX.html).
   

NG	REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR

OK

6.REPLACE CLEARANCE WARNING ECU

1. Replace the clearance warning ECU (CAMRY_ACV40 RM000001PYJ00TX.html).
   

NEXT

7.CHECK DTC OUTPUT

1. Clear DTCs.
   

2. Check for the DTC.
   

   Result:

   Result	Proceed to
   B2326 not output	A
   B2326 output	B

B	REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)

A
END

8.CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (CAN NO. 3 J/C - MAIN BODY ECU)

1. Disconnect the CAN MS bus main wire connector (O32) from the No. 3 CAN J/C.
   

HINT:

O32 connector color: White

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O32-1 (CANH) - O32-2 (CANL)	Ignition switch off	108 to 132 Ω

   Result:

   Result	Proceed to
   OK (w/ Entry and start system)	A
   OK (w/o Entry and start system)	B
   NG	C

B	REPLACE CAN NO. 3 J/C
C	Go to step 11

A

9.CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

1. Reconnect the certification ECU main wire connector (O32) to the No. 3 CAN J/C.
   

2. Disconnect the certification ECU main wire connector (O33) from the No. 3 CAN J/C.
   

   HINT:

   O33 connector color: Gray

3. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O33-1 (CANH) - O33-2 (CANL)	Ignition switch off	108 to 132 Ω

NG	Go to step 10

OK
REPLACE CAN NO. 3 J/C

10.CHECK OPEN IN CAN BUS MAIN WIRE

1. Disconnect the certification ECU connector (E74).
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E74-27 (CANH) - E74-28 (CANL)	Ignition switch off	108 to 132 Ω

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CERTIFICATION ECU - CAN NO. 3 J/C)

OK
REPLACE CERTIFICATION ECU

11.CHECK FOR OPEN IN CAN BUS MAIN WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

1. Reconnect the CAN MS bus main wire connector (O32) to the No. 3 CAN J/C.
   

2. Disconnect the main body ECU connector (E8) from the main body ECU.
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E8-16 (CANP) - E8-15 (CANN)	Ignition switch off	108 to 132 Ω

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)

OK
REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)

12.CHECK FOR SHORT IN CAN MS BUS WIRES (CAN NO. 3 J/C WIRE)

1. Disconnect the CAN MS bus main wire connector (O32) from the No. 3 CAN J/C.
   

HINT:

O32 connector color: White

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O32-1 (CANH) - O32-2 (CANL)	Ignition switch off	108 to 132 Ω

   Result:

   Result	Proceed to
   OK (w/ Entry and start system)	A
   OK (w/o Entry and start system)	B
   NG	C

B	Go to step 15
C	Go to step 17

A

13.CHECK FOR SHORT IN CAN MS BUS WIRES (CERTIFICATION ECU MAIN WIRE)

1. Disconnect the certification ECU main wire connector (O33) from the No. 3 CAN J/C.
   

   HINT:

   O33 connector color: Gray

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O33-1 (CANH) - O33-2 (CANL)	Ignition switch off	108 to 132 Ω

OK	Go to step 15

NG

14.CHECK FOR SHORT IN CAN MS BUS WIRES (CERTIFICATION ECU - CAN NO. 3 J/C)

1. Reconnect the certification ECU main wire connector (O33) to the No. 3 CAN J/C.
   

2. Disconnect the certification ECU connector (E74).
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E74-27 (CANH) - E74-28 (CANL)	Ignition switch off	108 to 132 Ω

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CERTIFICATION ECU - CAN NO. 3 J/C)

OK
REPLACE CERTIFICATION ECU

15.CHECK FOR SHORT IN CAN MS BUS WIRES (CLEARANCE WARNING ECU BRANCH WIRE)

1. Reconnect the certification ECU main wire connector (O33) to the No. 3 CAN J/C.
   

2. Disconnect the clearance warning ECU connector (O28).
   

3. Disconnect the main body ECU main wire connector (O31) from the No. 3 CAN J/C.
   

   HINT:

   O31 connector color: Blue

4. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O31-1 (CANH) - O31-2 (CANL)	Ignition switch off	1 MΩ or higher

OK	REPAIR OR REPLACE CAN MS BUS BRANCH WIRE OR CONNECTOR (CLEARANCE WARNING ECU - CAN NO. 3 J/C)

OK

16.CHECK FOR SHORT IN CAN MS BUS WIRES (CLEARANCE WARNING ECU)

1. Reconnect the main body ECU main wire connector (O31) to the No. 3 CAN J/C.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O28-3 (R1) - O28-5 (R2)	Ignition switch off	54 to 69 Ω

NG	REPLACE CAN NO. 3 J/C

OK
REPLACE CERTIFICATION ECU

17.CHECK FOR OPEN IN CAN BUS MAIN WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

1. Reconnect the CAN MS bus main wire connector (O32) to the No. 3 CAN J/C.
   

2. Disconnect the main body ECU connector (E8) from the main body ECU.
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E8-16 (CANP) - E8-15 (CANN)	Ignition switch off	108 to 132 Ω

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)

OK
REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)

18.CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CAN NO. 3 J/C WIRE)

1. Disconnect the CAN MS bus main wire connector (O32) from the No. 3 CAN J/C.
   

   HINT:

   O32 connector color: White

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O32-1 (CANH) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher
   O32-2 (CANL) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher

   Result:

   Result	Proceed to
   OK (w/ Entry and start system)	A
   OK (w/o Entry and start system)	B
   NG	C

B	Go to step 20
C	Go to step 22

A

19.CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

1. Disconnect the certification ECU main wire connector (O33) from the No. 3 CAN J/C.
   

   HINT:

   O33 connector color: Gray

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O33-1 (CANH) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher
   O33-2 (CANL) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher

NG	Go to step 21

OK

20.CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CLEARANCE WARNING ECU - CAN NO. 3 J/C)

1. Disconnect the clearance warning ECU connector (O28).
   

2. Disconnect the clearance warning ECU branch wire connector (O31) from the No. 3 CAN J/C.
   

   HINT:

   O31 connector color: Blue

3. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O31-1 (CANH) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher
   O31-2 (CANL) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher

NG	REPAIR OR REPLACE CAN MS BUS BRANCH WIRE OR CONNECTOR (CLEARANCE WARNING ECU BRANCH WIRE)

OK
REPLACE CLEARANCE WARNING ECU

21.CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

1. Disconnect the certification ECU connector (E74).
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O33-1 (CANH) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher
   O33-2 (CANL) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CERTIFICATION ECU MAIN WIRE)

OK
REPLACE CERTIFICATION ECU

22.CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

1. Disconnect the main body ECU connector E8 from the main body ECU.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O32-1 (CANH) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher
   O32-2 (CANL) - E10-16 (BAT)	Ignition switch off	6 kΩ or higher

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)

OK
REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)

23.CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CAN NO. 3 J/C WIRE)

1. Disconnect the CAN MS bus main wire connector (O32) from the No. 3 CAN J/C.
   

   HINT:

   O32 connector color: White

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O32-1 (CANH) - E10-4 (CG)	Ignition switch off	200 Ω or higher
   O32-2 (CANL) - E10-4 (CG)	Ignition switch off	200 Ω or higher

   Result:

   Result	Proceed to
   OK (w/ Entry and start system)	A
   OK (w/o Entry and start system)	B
   NG	C

B	Go to step 25
C	Go to step 27

A

24.CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)

1. Disconnect the certification ECU main wire connector (O33) from the No. 3 CAN J/C.
   

   HINT:

   O33 connector color: Gray

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O33-1 (CANH) - E10-4 (CG)	Ignition switch off	200 Ω or higher
   O33-2 (CANL) - E10-4 (CG)	Ignition switch off	200 Ω or higher

NG	Go to step 26

OK

25.CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CLEARANCE WARNING ECU - CAN NO. 3 J/C)

1. Disconnect the clearance warning ECU connector (O28).
   

2. Disconnect the clearance warning ECU branch wire connector (O31) from the No. 3 CAN J/C.
   

   HINT:

   O32 connector color: Blue

3. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O31-1 (CANH) - E10-4 (CG)	Ignition switch off	200 Ω or higher
   O31-2 (CANL) - E10-4 (CG)	Ignition switch off	200 Ω or higher

NG	REPAIR OR REPLACE CAN MS BUS BRANCH WIRE OR CONNECTOR (CLEARANCE WARNING ECU)

OK
REPLACE CLEARANCE WARNING ECU

26.CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CERTIFICATION ECU - CAN NO . 3 J/C)

1. Disconnect the certification ECU connector (E74).
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O33-1 (CANH) - E10-4 (CG)	Ignition switch off	200 Ω or higher
   O33-2 (CANL) - E10-4 (CG)	Ignition switch off	200 Ω or higher

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CERTIFICATION ECU MAIN WIRE)

OK
REPLACE CERTIFICATION ECU

27.CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (MAIN BODY ECU - CAN NO. 3 J/C)

1. Disconnect the main body ECU connector E8 from the main body ECU.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   O32-1 (CANH) - E10-4 (CG)	Ignition switch off	200 Ω or higher
   O32-2 (CANL) - E10-4 (CG)	Ignition switch off	200 Ω or higher

NG	REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)

OK
REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)

28.CHECK CAN BUS MAIN WIRE (CERTIFICATION ECU)

1. Disconnect the E74 certification ECU connector.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E74-27 (CANH) - E74-28 (CANL)	Ignition switch off	108 to 132 Ω

NG	Go to step 29

OK
REPLACE CERTIFICATION ECU

29.CHECK CAN BUS MAIN WIRE (MAIN BODY ECU - CERTIFICATION ECU)

1. Reconnect the certification ECU connector.
   

2. Disconnect the E8 main body ECU connector.
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E8-16 (CANP) - E8-15 (CANN)	Ignition switch off	108 to 132 Ω

NG	REPAIR OR REPLACE CAN BUS MAIN WIRE (MAIN BODY ECU - CERTIFICATION ECU)

OK
REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)

30.CHECK CAN BUS MAIN WIRE (CERTIFICATION ECU)

1. Disconnect the E74 certification ECU connector.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E74-27 (CANH) - E74-17 (E)	Ignition switch off	200 Ω or higher
   E74-28 (CANL) - E74-17 (E)	Ignition switch off	200 Ω or higher
   E74-27 (CANH) - E74-1 (+B)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
   E74-28 (CANL) - E74-1 (+B)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher

NG	Go to step 31

OK
REPLACE CERTIFICATION ECU

31.CHECK CAN BUS MAIN WIRE (MAIN BODY ECU - CERTIFICATION ECU)

1. Disconnect the E8 main body ECU connector.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard resistance:

   Tester Connection	Condition	Specified Value
   E74-27 (CANH) - E74-17 (E)	Ignition switch off	200 Ω or higher
   E74-28 (CANL) - E74-17 (E)	Ignition switch off	200 Ω or higher
   E74-27 (CANH) - E74-1 (+B)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher
   E74-28 (CANL) - E74-1 (+B)	Cable disconnected from negative (-) battery terminal	6 kΩ or higher

NG	REPAIR OR REPLACE CAN BUS MAIN WIRE (MAIN BODY ECU - CERTIFICATION ECU)

OK
REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)