Noise Troubleshooting Card

Illustration in preparation Description: One-page flowchart: symptom description → quick tests → most likely fix; three main branches for alternator whine, ignition noise, and hiss

NOISE DIAGNOSIS QUICK CHART

RPM-related whine (tone, changes with engine speed):
└─ Disconnect RCA at amp
   ├─ Noise stops → Ground loop → Fix amp ground, then head unit ground
   └─ Noise continues → Power line noise → Add inline filter, check alternator

Clicking/popping (irregular, changes with RPM):
└─ Move RCA away from power wire
   ├─ Better → EMI coupling → Re-route RCAs, add ferrite cores
   └─ Same → Ignition source → Check plug wires, route RCA away from engine

Constant hiss (same regardless of RPM):
└─ Turn volume to 0 at head unit
   ├─ Hiss stops → Gain too high → Reduce gain, re-calibrate
   └─ Hiss continues → Disconnect RCA at amp
      ├─ Hiss stops → Noise from source → Reduce gain
      └─ Hiss continues → Amp internal noise → Replace amp