Test E: Loud Popping Sound When Cycling The Ignition Switch

PINPOINT TEST E: LOUD POPPING SOUND WHEN CYCLING THE IGNITION SWITCH

E1-E3:

E3 Continued:

Normal Operation
When the key is cycled to START, voltage is sent to the audio unit through circuit 29-MD25 (OG/BK). When the audio unit receives this voltage signal, it disables the subwoofer amplifier by removing voltage from circuit 8-MD19 (WH/RD). This eliminates popping when the key is cycled.

Possible Causes
- Fuse
- Circuit 8-MD19 (WH/RD) short to voltage
- Circuit 29-MD25 (OG/BK) open
- Subwoofer amplifier
- Audio unit.