DTC    B15D0    MOST Communication Malfunction

for Preparation Click here

DESCRIPTION

HINT:

1. If a short occurs in a speaker circuit, the sound from the corresponding speaker will be low or almost impossible to hear. If the volume is turned up in this situation, to prevent excessive current flow due to the short circuit, the stereo component amplifier assembly stops operating when its output exceeds a certain level. When the operation of the stereo component amplifier assembly stops, the navigation system will not function normally. This is because MOST communication will stop due to the shut down of the amplifier causing an error in the MOST network. The stereo component amplifier assembly will start operating again when the power switch is turned off and back on (ACC) again. However, the amplifier will stop operating again if its output exceeds a certain level. (for 13 speakers)
   
2. When the stereo component amplifier assembly stops operating and a malfunction occurs in the navigation system due to a short in a speaker circuit, this DTC will be stored. (for 13 speakers)
   

HINT:

1. For the MOST network, the navigation computer sub-assembly is the master unit.
   
2. Errors may occur in MOST communication between devices due to problems such as electrical noise.
   

WIRING DIAGRAM

INSPECTION PROCEDURE

1. Choose the model to be inspected.
   

   Result:

   Model	Proceed to
   for 13 speakers	A
   except 13 speakers	B

B	Go to step 3

A

1. Power switch off.
   

2. Turn the power switch on (ACC) and check if the audio system activates and if the speakers operate.
   

   HINT:

   1. Choose a source such as radio so that sound can be output from the speakers.
      
   2. If sound from the speakers is low, turn up the volume.
      

   Result:

   Model	Proceed to
   The audio system activates when the power switch is turned on (ACC) but the sound stops being output when the amplifier output exceeds a certain level.	A
   Even after the power switch is turned on (ACC), the audio system does not activate and sound is not output from the speakers.	B

   HINT:

   1. If a short occurs in a speaker circuit, the sound from the corresponding speaker will be low or almost impossible to hear. If the volume is turned up in this situation, to prevent excessive current flow due to the short circuit, the stereo component amplifier assembly stops operating when its output exceeds a certain level. When the operation of the stereo component amplifier assembly stops, the navigation system will not function normally. This is because MOST communication will stop due to the shut down of the amplifier causing an error in the MOST network. The stereo component amplifier assembly will start operating again when the power switch is turned off and back on (ACC) again. However, the amplifier will stop operating again if its output exceeds a certain level.
      
   2. When the stereo component amplifier assembly stops operating and a malfunction occurs in the navigation system due to a short in a speaker circuit, this DTC will be stored. In this case, check each speaker circuit and repair or replace malfunctioning parts, and then recheck for DTCs.
      

B	Go to step 3

A
GO TO AUDIO AND VISUAL SYSTEM (w/ Navigation System) (Click here)

1. Display the "MOST Line Check" screen (Click here).
   

2. Check the result on the "MOST Line Check" screen.
   

   Result:

   Result	Proceed to
   "NCON" is displayed for "AUDIO".	A
   "NCON" is displayed for "AMP".	B
   "NCON" is displayed for "R-TOUCH".	C
   "OK" is displayed for all items.	D

   HINT:

   1. When "NCON" is displayed for more than 1 item, proceed to the step for the device that has the smallest node position number.
      
   2. The "MOST Line Check" screen can be displayed only when DTC B15D0 is stored.
      

B	Go to step 7
C	Go to step 10
D	Go to step 13

A

1. Check the MOST communication line connectors.
   

   1. Check if the MOST communication line connector between the navigation computer sub-assembly and radio receiver assembly has any connection problems (Click here).
      

2. Display the "MOST Line Check" screen and check the result (Click here).
   

   Result:

   Result	Proceed to
   "NCON" is displayed for "AUDIO".	A
   The screen cannot be changed to the "MOST Line Check" screen.	B

   HINT:

   When the malfunction in the MOST network is repaired, the screen cannot be changed to the "MOST Line Check" screen.

B	END

A

1. Disconnect the H50 radio receiver assembly connector.
   

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

   Standard Voltage:

   Tester Connection	Condition	Specified Condition
   H50-12 (WUI) - Body ground	Power switch on (ACC)	4.5 V or higher

NG	Go to step 6

OK
REPLACE RADIO RECEIVER ASSEMBLY (Click here)

1. Disconnect the H50 radio receiver assembly connector.
   

2. Disconnect the H62 navigation computer sub-assembly connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   H50-12 (WUI) - H62-8 (WUO)	Always	Below 1 Ω
   H50-12 (WUI) - Body ground	Always	10 kΩ or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
REPLACE NAVIGATION COMPUTER SUB-ASSEMBLY (Click here)

1. Check the MOST communication line connectors.
   

   1. Check if the MOST communication line connector between the radio receiver assembly and stereo component amplifier assembly has any connection problems (Click here).
      

2. Display the "MOST Line Check" screen and check the result (Click here).
   

   Result:

   Result	Proceed to
   "NCON" is displayed for "AMP".	A
   The screen cannot be changed to the "MOST Line Check" screen.	B

   HINT:

   When the malfunction in the MOST network is repaired, the screen cannot be changed to the "MOST Line Check" screen.

B	END

A

1. Disconnect the H56 stereo component amplifier assembly connector.
   

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

   Standard Voltage:

   Tester Connection	Condition	Specified Condition
   H56-3 (WUI) - Body ground	Power switch on (ACC)	4.5 V or higher

NG	Go to step 9

OK
REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY (Click here)

1. Disconnect the H56 stereo component amplifier assembly connector.
   

2. Disconnect the H50 radio receiver assembly connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   H56-3 (WUI) - H50-26 (WUO)	Always	Below 1 Ω
   H56-3 (WUI) - Body ground	Always	10 kΩ or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
REPLACE RADIO RECEIVER ASSEMBLY (Click here)

1. Check the MOST communication line connectors.
   

   1. Check if the MOST communication line connector between the stereo component amplifier assembly and remote touch has any connection problems (Click here).
      

2. Display the "MOST Line Check" screen and check the result (Click here).
   

   Result:

   Result	Proceed to
   "NCON" is displayed for "R-TOUCH".	A
   The screen cannot be changed to the "MOST Line Check" screen.	B

   HINT:

   When the malfunction in the MOST network is repaired, the screen cannot be changed to the "MOST Line Check" screen.

B	END

A

1. Disconnect the H71 remote touch connector.
   

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

   Standard Voltage:

   Tester Connection	Condition	Specified Condition
   H71-8 (WUI) - Body ground	Power switch on (ACC)	4.5 V or higher

NG	Go to step 12

OK
REPLACE REMOTE OPERATION BOARD (Click here)

1. Disconnect the H71 remote touch connector.
   

2. Disconnect the H56 stereo component amplifier assembly connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   H71-8 (WUI) - H56-9 (WUO)	Always	Below 1 Ω
   H71-8 (WUI) - Body ground	Always	10 kΩ or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY (Click here)

1. Disconnect the H62 navigation computer sub-assembly connector.
   

2. Disconnect the H50 radio receiver assembly connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   H62-3 (MO+) - H50-9 (MI+)	Always	Below 1 Ω
   H62-7 (MO-) - H50-23 (MI-)	Always	Below 1 Ω
   H62-6 (SLDO) - H50-10 (SLDI)	Always	Below 1 Ω
   H62-8 (WUO) - H50-12 (WUI)	Always	Below 1 Ω
   H62-3 (MO+) - Body ground	Always	10 kΩ or higher
   H62-7 (MO-) - Body ground	Always	10 kΩ or higher
   H62-6 (SLDO) - Body ground	Always	10 kΩ or higher
   H62-8 (WUO) - Body ground	Always	10 kΩ or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

1. Disconnect the H50 radio receiver assembly connector.
   

2. Disconnect the H56 stereo component amplifier assembly connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   H50-11 (MO+) - H56-4 (MI+)	Always	Below 1 Ω
   H50-25 (MO-) - H56-10 (MI-)	Always	Below 1 Ω
   H50-24 (SLDI) - H56-5 (SLDI)	Always	Below 1 Ω
   H50-26 (WUO) - H56-3 (WUI)	Always	Below 1 Ω
   H50-11 (MO+) - Body ground	Always	10 kΩ or higher
   H50-25 (MO-) - Body ground	Always	10 kΩ or higher
   H50-24 (SLDI) - Body ground	Always	10 kΩ or higher
   H50-26 (WUO) - Body ground	Always	10 kΩ or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

1. Disconnect the H56 stereo component amplifier assembly connector.
   

2. Disconnect the H71 remote touch connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   H56-6 (MO+) - H71-6 (MI+)	Always	Below 1 Ω
   H56-12 (MO-) - H71-5 (MI-)	Always	Below 1 Ω
   H56-11 (SLDO) - H71-7 (SLDI)	Always	Below 1 Ω
   H56-9 (WUO) - H71-8 (WUI)	Always	Below 1 Ω
   H56-6 (MO+) - Body ground	Always	10 kΩ or higher
   H56-12 (MO-) - Body ground	Always	10 kΩ or higher
   H56-11 (SLDO) - Body ground	Always	10 kΩ or higher
   H56-9 (WUO) - Body ground	Always	10 kΩ or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

1. Disconnect the H71 remote touch connector.
   

2. Disconnect the H62 navigation computer sub-assembly connector.
   

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

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   H71-1 (MO+) - H62-1 (MI+)	Always	Below 1 Ω
   H71-2 (MO-) - H62-5 (MI-)	Always	Below 1 Ω
   H71-3 (SLDO) - H62-2 (SLDI)	Always	Below 1 Ω
   H71-1 (MO+) - Body ground	Always	10 kΩ or higher
   H71-2 (MO-) - Body ground	Always	10 kΩ or higher
   H71-3 (SLDO) - Body ground	Always	10 kΩ or higher

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

1. Replace the remote operation board (Click here).
   

2. Clear the DTCs (Click here).
   

3. Recheck for DTCs and check if the same DTCs are output again.
   

   Result:

   Result	Proceed to
   No DTCs are output.	A
   DTCs are output.	B

B	Go to step 18

A
END

1. Replace the stereo component amplifier assembly (Click here).
   

2. Clear the DTCs (Click here).
   

3. Recheck for DTCs and check if the same DTCs are output again.
   

   Result:

   Result	Proceed to
   No DTCs are output.	A
   DTCs are output.	B

B	Go to step 19

A
END

1. Replace the radio receiver assembly (Click here).
   

2. Clear the DTCs (Click here).
   

3. Recheck for DTCs and check if the same DTCs are output again.
   

   Result:

   Result	Proceed to
   No DTCs are output.	A
   DTCs are output.	B

B	REPLACE NAVIGATION COMPUTER SUB-ASSEMBLY (Click here)

A
END