Sound Signal Circuit Between Stereo Component Tuner Assembly And Multi-Media Interface ECU: Procedure

1. Disconnect the D67 multi-media interface ECU connector.
   Fig 1: Checking Multi-Media Interface ECU

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2. Using an oscilloscope, check the signal waveform between each terminal and the body ground according to the conditions, as shown in the chart below.

   OK

   Tester Connection	Condition	Specified Condition
   D67-7 (ULI+) - Body ground	Audio sound is being produced	A waveform synchronized with sound is output
   D67-8 (URI+) - Body ground
   D67-15 (ULI-) - Body ground
   D67-16 (URI-) - Body ground

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Multi-Media Interface ECU)

NG → See step   2 

OK → See step   3 

1. Disconnect the L20 stereo component tuner assembly connector.
2. Disconnect the D67 multi-media interface ECU connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D67-7 (ULI+) - L20-4 (FLO+)	Always	Below 1 Ω
   D67-8 (URI+) - L20-2 (FRO+)	Always	Below 1 Ω
   D67-15 (ULI-) - L20-5 (FLO-)	Always	Below 1 Ω
   D67-16 (URI-) - L20-3 (FRO-)	Always	Below 1 Ω
   L67-6 (USD2) - Body ground	Always	10 kΩ or higher
   D67-7 (ULI+) - Body ground	Always	10 kΩ or higher
   D67-8 (URI+) - Body ground	Always	10 kΩ or higher
   D67-15 (ULI-) - Body ground	Always	10 kΩ or higher
   D67-16 (URI-) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   4