Test F: Loud Popping Sound From The Speakers

PINPOINT TEST F: LOUD POPPING SOUND FROM THE SPEAKERS

F1:

F1-F3:

Normal Operation
The START input circuit 1003 (GY/YE) is sent to the audio unit when the ignition switch is turned to the START position. The audio unit then immediately mutes all speaker amplifier outputs and the subwoofer amplifier enable circuit output to eliminate the possibility of speaker pops during engine cranking.

Possible Causes
- circuit 1003 (GY/YE) open or short to voltage
- circuit 168 (RD/BK) short to voltage
- subwoofer amplifier
- audio unit