Audio System: Troubleshooting

DIAGNOSIS FUNCTION
1. Diagnosis mode start-up:
  When the audio power is OFF and ACC is ON, push DISC or CD button 3 times with 1 and 6 of TRUCK TUNE APS buttons simultaneously pressed. Then, the audio system enters into the diagnosis mode.
  
  NOTE: To exit from the diagnosis mode, press DISC or CD button for 1.7 seconds or turn the ignition switch OFF.
  
  Fig 1: Identifying Radio Receiver Switches
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Element lighting mode:
  1. After the audio system has entered into the diagnosis mode, the system automatically goes into the element lighting mode and causes all the elements on the LCD to light up. During this mode, all the elements remain on.
  2. Check if the elements function properly. If the elements light up, they are functioning properly.
  3. Check if the buttons function properly by pushing them. If a beep sound (3 kHZ, 50ms) is heard when one of the buttons is pushed, this button is functioning properly.
    NOTE: If SEEK UP button is pressed, the system will enter into the service check mode.
3. Service check mode:
  1. During the element lighting mode, push SEEK UP button. Then, the audio system enters into the service check mode.
  2. Check the error codes on the LCD.
  NOTE:
  - The present and past conditions of the components can be checked by performing the System Check and collecting the stored DTC memories.
  - There are 6 types of error codes: "good", "nCon", "CHEC", "ECHn", "Old" and "nrES".
  - good (Good):
    No DTC is detected by both "System Check Confirmation" command and "Diagnosis Memory Response" command.
  - nCon (No Connection):
    There is a component which does not respond to the "Diagnosis On Instruction" command. This error code is applicable to only the system where the connected components are limited to be used.
  - ECHn (Exchange):
    Application of new diagnosis version has been confirmed by the "Diagnosis On Check" command. One or more DTC which indicates "Replacement" has been detected by the "System Check Result Response" command or the "Diagnosis Memory Response" command.
  - CHEC (Check):
    Application of the new diagnosis version has been confirmed by the "Diagnosis On Check" command. No DTC which indicates "Replacement" has been detected by the "System Check Result Response" command, or the "Diagnosis Memory Response" command, but one or more DTC which indicated "Check" has been detected.
  - Old (Old):
    Application of old diagnosis version has been confirmed by the "Diagnosis On Check" command. DTC has been detected by the "System Check Result Response" command or the "Diagnosis Memory Response" command.
  - nrES (No response):
    No response has been identified by the "System Check Start Instruction" command, the "Request for System Check Result" command or the "Request for Diagnosis Memory" command.
4. Display Screen for Service Check.
  
  Fig 2: Service Check Flow On Display Screen
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  - If diagnosis memory is cleared during service check mode, diagnosis information of all components will be cleared and system will return to service check mode (Refer to ( i)).
  - After the memory is cleared, only the physical address is displayed cyclically.
  - When re-checking (ch1 button is pressed) in that condition, the result is also displayed as shown above.
5. "ECHn" Detail Disolav Mode Screen
  
  Fig 3: "ECHn" Detail Flow On Display Mode Screen
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. "CHEC" Detail Display Mode Screen
  
  Fig 4: "CHEC" Detail Flow On Display Mode Screen
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
7. "OLD" Detail Display Mode Screen
  
  Fig 5: "OLD" Detail Flow On Display Mode Screen
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
8. Recheck:
  To perform a recheck, push ch1 during the service check mode.
  
  NOTE:
  For the recheck process, refer to the Display Screen for Service Check (step d).
9. Memory clear mode:
  1. Clear the diagnosis memory during Service Check Mode:
    Push ch5 for 1.7 sec. during the service check mode. Then the diagnosis information of all the components is cleared and a beep sound is heard for 3 sec.
    NOTE:
    After the diagnosis information has been cleared, the system returns to the service check mode and only the physical addresses of all the connected components are displayed. Since all the diagnosis information is cleared, no error code is displayed.
    
    If a recheck is executed under this condition, the check results will be displayed as usual.
  2. Clear the diagnosis memory during Detail Display Mode:
  Push ch5 for 1.7 sec. during the detail display modes. Then the diagnosis information of applicable component is cleared and a beep sound is heard for 3 sec.
  NOTE:
  - After the diagnosis information has been cleared, the system returns to the service check mode and only the physical addresses of the applicable component is displayed.
  - Since all the diagnosis information is cleared, no error code is displayed.
  - If a recheck is executed under this condition, the check results will be displayed as usual, (j) Separate display of "System Check Result Response" command and "Diagnosis Memory Response" command:
    NOTE:
    During the detail display modes, diagnosis information detected by both the "System Check Result Response" command and "Diagnosis Memory Response" command is displayed separately.
    
    For display of the diagnosis information detected by the "System Check Result Response" command, "SyS is displayed at first, and then detailed information (multiple codes) are displayed in order.
    
    For display of the diagnosis information detected by the "Diagnosis Memory Response" command, "COdE" is displayed at first, and then detailed information (multiple codes) are displayed in order.

DIAGNOSTIC TROUBLE CODE LIST

TERMS MEANING

Terms	Meaning
Physical Address	Three-Digit Code (Shown In Hexadecimal) Which Is Given To Each Component Comprising The AVC-LAN. Corresponding To The Function, Individual Symbols Are Specified.
Logical Address	Two-Digit Code (Shown In Hexadecimal) Which Is Given To Each Function Comprising The Inner System Of The AVC-LAN.

Physical address: 190 Radio receiver assembly
NOTE:
- *1: Even if no failure is detected, it may be stored depending on the battery condition or voltage for starting the engine.
- *2: It is stored when 180 seconds have passed after the power supply connector is pulled out after the engine is started.
- *3: It may be stored when the ignition key is turned 1 minute again the after engine is started.
- *4: It may be stored when the ignition key is turned again after the engine is started.
- *5: When 210 seconds have passed after disconnecting the power supply connector of the master component with the ignition switch in ACC or ON, this code is stored.
1. Logical address: 01 (Communication control)
  
  Fig 6: DTC List - Logical Address: 01 (Communication Control)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Logical address: 61 (Cassette switch)
3. Logical address: 62 (CD player)
4. Logical address: 63 (CD changer)
  
  Fig 9: DTC List - Logical Address: 63 (CD Changer)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Physical address: 440 Stereo component amplifier
NOTE:
- *1: Even if no failure is detected, it may be stored depending on the battery condition or voltage for starting the engine.
- *2: It may be stored when the ignition key is turned 1 minute again after the engine is started.
- *3: It may be stored when the ignition key is turned again after the engine is started.
- *4: When 210 seconds have passed after disconnecting the power supply connector of the master component with the ignition switch in ACC or ON, this code is stored. Logical address: 01 (Communication control)
Fig 10: DTC List - Logical Address: 01 (Communication Control)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Physical address: 360 CD Changer
NOTE:
- *1: Even if no failure is detected, it may be stored depending on the battery condition or voltage for starting the engine.
- *2: It may be stored when the ignition key is turned 1 minute again after the engine is started.
- *3: It may be stored when the ignition key is turned again after the engine is started.
- *4: It may be stored when the ignition key is turned again after the engine is started.
- *5: When 210 seconds have passed after disconnecting the power supply connector of the master component with the ignition switch in ACC or ON, this code is stored. Logical address: 01 (Communication control)
Fig 11: DTC List - Logical Address: 01 (Communication Control)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

PROBLEM SYMPTOMS TABLE

CAUTION: When replacing the internal mechanism (computer part) of the audio system, be careful that no part of your body or clothing comes in contact with the terminals of the leads from the IC, etc. of the replacement part (spare part).

NOTE:

This inspection procedure is a simple troubleshooting which should be carried out on the vehicle while the system is operating on the assumption that the system component has troubles (except for the wires and connectors, etc.).

Take the following items into consideration during inspection.

Open or short circuit of the wire harness
Connector or terminal connection fault

PROBLEM SYMPTOMS

Problem		No.
Radio	Radio Does Not Operate When Power Switch Is Turned To 'ON'.	Fig 12
.....	Display Indicates When Power Switch Is Turned To 'ON', But No Sound (Including 'noise') Is Produced.	Fig 13
.....	Noise Is Present, But AM - FM Does Not Operate.	Refer To #3 In Fig 14
.....	Any Speaker Does Not Work.	Refer To #4 In Fig 14
.....	Any AM Or FM Does Not Work.	Fig 15
.....	Few Preset Tuning Bands.	Fig 15
.....	Reception Is Poor.	Fig 16
.....	Sound Quality Is Poor.	Fig 17
.....	Preset Memory Disappears.	Fig 18
Tape Player	Cassette Tape Cannot Be Inserted.	Fig 19
.....	Cassette Tape Can Be Inserted, But No Power Is Produced.	Fig 20
.....	Power Comes In, But Tape Player Does Not Operate.	Fig 21
.....	Any Speaker Does Not Work.	Fig 22
.....	Sound Quality Is Poor.	Fig 23
.....	Tape Is Jammed, Malfunction With Tape Speed Or Auto-Reverse.	Fig 24
.....	Cassette Tape Can Not Be Ejected.	Fig 25
CD Player	CD Cannot Be Inserted.	Fig 26
.....	CD Can Be Inserted, But No Power Is Produced.	Fig 27
.....	Power Comes In, But CD Player Does Not Operate.	Fig 28
.....	Sound Jumps.	Fig 29
.....	Sound Quality Is Poor (Volume Faint).	Fig 30
.....	Any Speaker Does Not Work.	Fig 31
.....	CD Can Not Be Ejected.	Fig 32
Power Amplifier	No Power Comes In.	Fig 33
.....	Power Comes In, But Woofer (Power) Amplifier Does Not Operating.	Fig 34
.....	Any Speaker Does Not Work.	Fig 35
Noise	Noise Occurs	Fig 36
.....	Noise Is Produced By Vibration Or Shock While Driving.	Fig 37
.....	Noise Is Produced When Engine Starts.	Fig 38

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

Fig 12: Radio Diagnostic Procedure (1 Of 27)