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Test I: No Sound From All Speakers

PINPOINT TEST I: NO SOUND FROM ALL SPEAKERS


I1:






I1-I3:






Normal Operation
The audio unit directs the audio signals to the speakers through separate positive and negative circuits for each of the four audio channels: LH front, RH front, LH rear, and RH rear. When the key is put in the START position, voltage is sent to the audio unit from the smart junction box (SJB) through circuit 1786 (BN/PK), at which time the audio unit mutes all speakers to reduce popping. The audio unit provides internal circuit protection for shorts to ground, shorts to B+ battery, or shorts between any output circuits.

Possible Causes
- Circuit 1786 (BN/PK) short to voltage
- Audio unit
- SJB