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Inspection Procedure

IDENTIFY THE COMPONENT SHOWN BY SUB-CODE
1. Enter the diagnostic mode.
  
  Fig 1: Service Check Mode And Detailed Information Mode Flow Chart
  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 sub-code 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 CHART

Component	Proceed to
Gateway ECU (1C6)	(See GATEWAY ECU POWER SOURCE CIRCUIT )
Stereo component amplifier (440)	(See STEREO COMPONENT AMPLIFIER POWER SOURCE CIRCUIT )
Television display assembly (1B0)	(See TELEVISION DISPLAY 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 SPECIFICATION

Tester connection	Condition	Specified condition
ATX+ - ATX-	Always	60 to 80 Ω
TX+ - TX-	Always	60 to 80 Ω
TX+ - TX-	Always	60 to 80 Ω

NG: REPLACE RADIO RECEIVER

Fig 2: Identifying Radio Receiver Connectors

G05280608

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: GO TO next step.

CHECK HARNESS AND CONNECTOR (RADIO RECEIVER - COMPONENT SHOWN BY SUB-CODE)
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 radio receiver and the component shown by the sub-code.
  1. Disconnect all connectors between the radio receiver and the component shown by the sub-code.
  2. Check for an open or short in the AVC-LAN circuit between the radio receiver and the component shown by the sub-code.
    OK: There is no open or short circuit.
Fig 3: AVC-LAN Wiring Diagram
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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 RADIO RECEIVER

OK: END