DTC B15D0-87: MOST Communication Missing Message [09/2022 - ]: Procedure

1. Using the GTS, check for DTCs.

   Body Electrical > Navigation System > Trouble Codes 

   Result

   Result	Proceed to
   Only DTC B15D0-87 is output	A
   DTC B15C3-71 is output	B
   DTC B15A3-87 is output	C

   HINT: 

   • If a short occurs in a speaker circuit, the sound output from the speakers will become very low or will stop and DTC B15C3-71 will be stored.

     In this case, if the audio system volume is increased, current in the speaker circuit will increase more than necessary.

     To prevent the current from becoming excessively high, when it increases to a certain amount, operation of the stereo component amplifier assembly will be suspended.

     If operation is suspended, MOST communication will become impossible, the audio and visual system will not operate normally and DTC B15D0-87 will be stored.

   • If DTC B15C3-71 and B15A3-87 are output at the same time, perform troubleshooting for DTC B15C3-71 first.

Result: 

B 

GO TO DTC B15C3-71. Refer to  DTC B15C3-71: Speaker Output Short Actuator Stuck [09/2022 - ]  

Result: 

C 

GO TO DTC B15A3-87. Refer to  DTC B15A3-87: Stereo Component Amplifier Missing Message [09/2022 - ]  

Result: 

A 

See step  2

1. Check the "MOST Line Check" result.

   Refer to DIAGNOSIS SYSTEM [09/2022 - ]

   1. Enter diagnostic mode.
   2. Select "System Check" from the "Service Menu" screen.
   3. Select "System Check Mode" from the " System Check " screen.
   4. Select "DETAIL" from the " System Check Mode " screen.
   5. Select "MOST" from the " Unit Check Mode " screen and check the "MOST Line Check" result.

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      *a	MOST Network Device Node Position Number
      *b	Device Name
      *c	Result

      HINT: 

      • It is only possible to transition to the "MOST line connection inspection" screen when the DTC is a latest DTC.
      • It is not possible to transition to the "MOST line connection inspection" screen when MOST communication has been established.

   Result

   Result	Proceed to
   "OK" is displayed for all items.	A
   "NCON" is displayed for "AMP".	B

Result: 

B 

See step  6

Result: 

A 

See step  3

1. Disconnect the G116 stereo component amplifier assembly connector.
2. Disconnect the G158 radio receiver assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G116-2 (MI+) - G158-5 (MO+)	Always	Below 1 Ω
   G116-3 (MI-) - G158-6 (MO-)	Always	Below 1 Ω
   G116-4 (SLDI) - G158-7 (SLDO)	Always	Below 1 Ω
   G116-5 (MO+) - G158-2 (MI+)	Always	Below 1 Ω
   G116-6 (MO-) - G158-3 (MI-)	Always	Below 1 Ω
   G116-7 (SLDO) - G158-4 (SLDI)	Always	Below 1 Ω
   G116-2 (MI+) or G158-5 (MO+) - Body ground	Always	10 kΩ or higher
   G116-3 (MI-) or G158-6 (MO-) - Body ground	Always	10 kΩ or higher
   G116-4 (SLDI) or G158-7 (SLDO) - Body ground	Always	10 kΩ or higher
   G116-5 (MO+) or G158-2 (MI+) - Body ground	Always	10 kΩ or higher
   G116-6 (MO-) or G158-3 (MI-) - Body ground	Always	10 kΩ or higher
   G116-7 (SLDO) or G158-4 (SLDI) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Replace the stereo component amplifier assembly with a new or known good one.

   Refer to REMOVAL [09/2022 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  5

1. Clear the DTCs.

   Body Electrical > Navigation System > Clear DTCs 

2. Turn the ignition switch off.
3. Turn the ignition switch to ON and wait for 30 seconds or more.
4. Turn the ignition switch off.
5. Turn the ignition switch to ON and wait for 30 seconds or more.
6. Check for DTCs.

   Body Electrical > Navigation System > Trouble Codes 

   Result

   Result	Proceed to
   No DTC is output	A
   DTC B15D0-87 is output	B

Result: 

A 

END (STEREO COMPONENT AMPLIFIER ASSEMBLY IS DEFECTIVE) 

Result: 

B 

REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [09/2022 - ] 

1. Disconnect the G116 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
   G116-8 (WUI) - Body ground	IG ON	4.5 V or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY. Refer to  REMOVAL [09/2022 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR