Poor Sound From All Speakers

Test 1 - 5:

Test 6 - 7:

SYMPTOM
POOR SOUND FROM ALL SPEAKERS

POSSIBLE CAUSES
- Fixed mast antenna
- Bad power amplifier connections
- Fused IGN run/ACCY CKT open
- Defogger/antenna module ground CKT open
- Rear defogger/antenna module
- Rear window antenna grid