Audio System: Troubleshooting

Fig 1: Identifying Audio System Components Example

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Starting Diagnosis Mode (all elements are lighting in the switch check mode)
   1. Turn off the audio system and turn the ignition switch to ACC. While pressing and holding down the preset switches "1" and "6", press "DISC" 3 times.
   2. Reference:
      • When the system enters the Diagnosis Mode, a "beep" tone is emitted 3 times and all the elements are lighting in the switch check mode.
      • It takes about 40 seconds to complete the check.
      • Turn all the elements in the LCD on.
      • When pressing the switch, confirm that a beep tone is emitted.
      • Press the "SEEK UP" switch to enter the "Service Check Screen".
2. Service Check Screen

   Reference:

   In the service check mode, the system check and the diagnosis memory check are performed. Check results are displayed in ascending order of the device codes (physical address.)

   TERMS & DEFINITIONS
   
   

   Terms	Meaning
   Component code (Physical address)	Three-digit code (in hexadecimal) given to each device comprising AVC-LAN. Corresponding to its function, individual symbol is provided.
   Logical address	Two-digit code (in hexadecimal) given to each function and device unit in each device comprising AVC-LAN.

   Code No. (physical address) List 

   CODE NO. LIST
   
   

   Code No. (physical address)	Equipment name
   190	Radio receiver (Audio head unit)
   440	Stereo component amplifier

3. Finishing Diagnosis Mode

   Press "DISC" for 2 seconds or more, or turn the ignition switch OFF.

4. The service Check Mode Result Display is for checking the current and the past system conditions.
   1. Press the "SEEK TRACK" switch to see the check result of each device.
      Fig 2: Identifying Service Check Mode Result Display

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Check Result Display.
      CHECK RESULT DISPLAY
      
      

      Display	Original Language	Meaning	Action to be taken
      good	Good (normal)	No DTCs are detected in both "System Check Mode" and "Diagnosis Memory Mode".
      NCON	No connection	The system recognized the component when it was registered, but the component gives no response to the "Diagnosis Mode ON Request".	Check the power source circuit and the communication circuit of the device indicated by the device code (physical address).
      ECHN	Exchange	One or more DTCs for "Exchange" is detected in either "System Check Mode" or "Diagnosis Memory Mode".	Go to the detailed information mode to check the trouble area referring to the DTC list.
      CHEC	Check	When no DTCs are detected for "Exchange", one or more DTC for "Check is detected in either "System Check Mode" or "Diagnosis Memory Mode".	Go to the detailed information mode to check the trouble area referring to the DTC list.
      OLD	Old version	Old DTC application is identified and DTC is detected in either "System Check Mode" or "Diagnosis Memory Mode".
      NRES	No response	The device gives no response to "System Check Mode ON Request", "System Check Result Request" and "Diagnosis Memory Request".	Check the power source circuit and the communication circuit of the device indicated by the device code (physical address).

   3. To perform the Service Check again, press the preset switch "1".
5. Detailed Information Mode (when displaying the troubled device's DTC).
   1. With "CHEC" or "ECHN" being displayed, press the preset switch "2" to go to the detailed information mode.
   2. Press the "SEEK TRACK" switch to display "System Check Result (SYS)" and "Diagnosis Memory Response (CODE)".
      Fig 3: Identifying Detailed Information Mode

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Displayed Items in Detailed Information Mode.
      Fig 4: Identifying Detailed Information Mode Chart

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   4. Check the trouble area by referring to the DTC list.
   5. To return to the service check mode, press the preset switch "3".
6. Clearing Individual DTC Memory (when clearing the memory of the DTC detected in the past individually).

   Press the preset switch "5" for 2 seconds or more while the "ECHN" is displayed in the service check mode or during the detailed information mode.

   HINT:

   • Beep sound is emitted once when the DTC memory is completely cleared.
   • When the DTC memory is cleared, only the component code (physical address) is displayed for the target component.
   • To check the DTC, press the preset switch "1" and perform the service check again.
7. Clearing all the DTC memory (when clearing all the memory of the DTC detected in the past).
   1. Start the diagnosis mode after repairing the trouble area.
   2. Press the preset switch "5" for 2 seconds or more. ("CLR" is displayed at this time.)

      HINT:

      • Beep sounds once when the DTC memory is completely cleared.
      • When the DTC memory for all the devices are cleared, only the component codes (physical address) are displayed.
   3. Press the preset switch "1" to perform the service check again, and check that no DTCs are displayed for all the component codes (physical address).

Fig 5: Terms & Meaning Table

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

Titles for each unit are stated in the following order: physical address (part name).

HINT:

• *¹ : Even if no failure is detected, trouble code may be stored depending on the battery condition or voltage for starting the engine.
• *² : The code is stored 180 seconds after the power supply connector is disconnected after engine start.
• *³ : The code may be stored when the engine key is turned 1 minute after engine start.
• *⁴ : The code may be stored when the engine key is turned again after engine start.
• *⁵ : The code is stored 210 seconds after the master component power supply connector is disconnected with the ignition switch in the ACC or ON position.

1. Logical address: 01 (Communication control)
   Fig 6: Communication Control Diagnosis Table

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Logical address: 61 (Cassette switch)
   Fig 7: Cassette Switch Diagnosis Table

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Logical address: 62 (CD player)
   Fig 8: CD Player Diagnosis Table

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

• *¹ : Even if no failure is detected, this code may be stored depending on the battery condition or voltage for starting the engine.
• *² : The code may be stored when the engine key is turned again 1 minute after engine start.
• *³ : The code may be stored when the engine key is turned again after engine start.
• *⁴ : The code is stored 210 seconds after the master component power supply is disconnected with the ignition switch in the ACC or ON position.

  Logical address: 01 (Communication control)

  Fig 9: Stereo Component Amplifier Communication Control Diagnosis Table

  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

This inspection procedure is a simple type of troubleshooting which should be carried out on the vehicle while the system is operating with a system component malfunctioning (except for the wires and connectors.

Take the following items into consideration during inspection.

• Open or short circuit of the wire harness
• Connector or terminal connection fault
  PROBLEM & CONNECTOR OR TERMINAL CONNECTION FAULT REFERENCE
  
  

  	Problem	No.
  Radio	Radio does not operate when power switch is turned to 'ON'.	1
  	Display indicates when power switch is turned to 'ON', but no sound (including 'noise') is produced.	2
  	Noise is present, but AM - FM does not operate.	3
  	One of the speakers does not work.	4
  	Either AM or FM does not work.	5
  	Reception is poor.	6
  	Sound quality is poor.	7
  	Preset memory disappears.	8
  Tape Player	Cassette tape cannot be inserted.	9
  	Cassette tape can be inserted, but no power is produced.	10
  	Power comes in, but tape player does not operate.	11
  	One of the speakers does not work.	12
  	Sound quality is poor (Volume faint).	13
  	Tape is jammed, malfunction with tape speed or auto-reverse.	14
  	Cassette tape cannot be ejected.	15
  CD Player	CD cannot be inserted.	16
  	CD can be inserted, but no power is produced.	17
  	Power turns on, but CD player does not operate.	18
  	CD skips and audio is not smooth.	19
  	Sound quality is poor (volume faint).	20
  	One of the speakers does not work.	21
  	CD cannot be ejected.	22
  Power Amplifier	No power turns on.	23
  	Power turns on, but woofer (power) amplifier does not operate.	24
  	One of the speakers does not work.	25
  Noise	Noise occurs.	26
  	Noise is produced by vibration or shock during driving.	27
  	Noise is produced when engine starts.	28

  The term "AM" includes LW, MW and SW, and the term "FW" includes UKW.