Stereo Component Amplifier Power Source Circuit: Procedure

1. Remove the RADIO NO. 1 fuse from the engine room No. 1 relay block.
2. Remove the RADIO NO. 2 fuse from the passenger side junction block.
3. Remove the AM1 fuse from the driver side junction block.
4. Measure the resistance of the fuses.

   Standard resistance

   Below 1 Ω

NG → REPLACE FUSE 

OK: Go to next step 

1. Disconnect the S22 and S23 amplifier connectors.
   Fig 1: Identifying S22 And S23 Connectors

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2. Measure the resistance and voltage of the wire harness side connectors.

   Standard resistance

   Standard voltage 

   Tester Connection	Specified Condition
   S22-13 (GND) - Body ground	Below 1 Ω
   S22-12 (E) - Body ground	Below 1 Ω

   Tester Connection	Condition	Specified Condition
   S22-7 (B+) - Body ground	Always	10 to 14 V
   S22-16 (B+) - Body ground	Always	10 to 14 V
   S23-20 (ACC) - Body ground	Ignition switch ACC	10 to 14 V

NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE