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Inspection Procedure

IDENTIFY THE COMPONENT SHOWN BY SUB-CODE
1. Enter the diagnostic mode.
  
  Fig 1: Detailed Information Mode And Service Check Mode - Communication Diagram
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Press the preset switch "3" to change to "Detailed Information Mode".
3. Identify the component shown by the sub-code.
  HINT:
  - "190 (radio receiver)" is the component shown by the subcode in the example shown in the illustration.
  - For details of the DTC display, refer to DTC CHECK/CLEAR .

CHECK POWER SOURCE CIRCUIT OF COMPONENT SHOWN BY SUB-CODE

Inspect the power source circuit of the component shown by the sub-code.
If the power source circuit is operating normally, proceed to the next step.

Component Table:

COMPONENT REFERENCE

Component	Proceed to
Integration control & panel assembly (1D8)	Integration control & panel assembly power source circuit (See INTEGRATION CONTROL AND PANEL ASSEMBLY POWER SOURCE CIRCUIT )
Stereo component amplifier (440)	Stereo component amplifier power source circuit (See STEREO COMPONENT AMPLIFIER POWER SOURCE CIRCUIT )
Radio receiver (190)	Radio receiver power source circuit (See RADIO RECEIVER POWER SOURCE CIRCUIT )

INSPECT RADIO RECEIVER

Disconnect the radio receiver connectors.

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

Standard resistance

RESISTANCE REFERENCE

Tester Connection	Condition	Specified Condition
ATX+ - ATX-	Always	60 to 80 Ω
TXM+ - TXM-	Always	60 to 80 Ω
TX+ - TX-	Always	60 to 80 Ω

Fig 2: Identifying Radio Receiver Connector Terminal

G05828128

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE RADIO RECEIVER

OK: Go to next step

CHECK HARNESS AND CONNECTOR (GATEWAY ECU - COMPONENT SHOWN BY SUBCODE)
HINT:
- Start the check from the circuit that is near the component shown by the sub-code first.
- For details of the connectors, refer to the TERMINALS OF ECU .
1. Referring to the AVC-LAN wiring diagram below, check the AVC-LAN circuit between the gateway ECU and the component shown by the sub-code.
  1. Disconnect all connectors between the gateway ECU and the component shown by sub-code.
  2. Check for an open or short in the AVC-LAN circuit between the gateway ECU and the component shown by the sub-code.
    OK:
    
    There is no open or short circuit.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step
REPLACE COMPONENT SHOWN BY SUB-CODE
1. Replace the component shown by the sub-code with a normal one and check if the same problem occurs again.
  OK:
  
  Same problem does not occur.
NG: REPLACE GATEWAY ECU

OK: END