C4 88 - Power interference on audio
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Joined: Aug 2023
Posts: 70
Likes: 26
From: Texas
C4 88 - Power interference on audio
Hi everyone,
I decided to fix the audio and replaced the head unit with Chinese android head unit with small screen. Previous audio (Boss) didn't work since purchase. When I installed everything - it works perfectly fine straight from the battery, without engine running. When I'm turning the engine - there are a lot of EM noise from speakers and screen on the head unit goes crazy (see the video on this link link to the video - first part with engine running and at the end - from battery only). And if lower the revs - then more crazy screen in noise goes.
I put 2 filters there:
1. For audio channel ( )
2. And another one for +12 power to the unit itself ( )
After installation - noise from speakers disappeared, but the screen still goes pretty crazy. What else can I do to fix that?
I decided to fix the audio and replaced the head unit with Chinese android head unit with small screen. Previous audio (Boss) didn't work since purchase. When I installed everything - it works perfectly fine straight from the battery, without engine running. When I'm turning the engine - there are a lot of EM noise from speakers and screen on the head unit goes crazy (see the video on this link link to the video - first part with engine running and at the end - from battery only). And if lower the revs - then more crazy screen in noise goes.
I put 2 filters there:
1. For audio channel ( )
2. And another one for +12 power to the unit itself ( )
After installation - noise from speakers disappeared, but the screen still goes pretty crazy. What else can I do to fix that?
Thread Starter
Advanced
Joined: Aug 2023
Posts: 70
Likes: 26
From: Texas
Yes, I did make a separate ground, both for Amp and Head unit. Gauge is 1/0 GA on Amp, so I think that should be fine. I'm thinking about the Alternator - can this be an issue (like ripple current, or so). It has good voltage (14.0-14.5) when idling though.
Thread Starter
Advanced
Joined: Aug 2023
Posts: 70
Likes: 26
From: Texas
Ok, seems like I found the root cause, but I don't know how to fix it.
For test purpose, I just connected only power and ground to the head unit outside the car - no interference when engine is running.
If I'm coming closer to the spark plug wires - it starts to interfere. I had similar issue with dashboard - it was flickering due to damaged insulation of the wire. I replaced them with the new set about few months ago and dashboard stopped flickering. But the stereo head unit is still interferes significantly when is closer to the engine bay. Any suggestions?
For test purpose, I just connected only power and ground to the head unit outside the car - no interference when engine is running.
If I'm coming closer to the spark plug wires - it starts to interfere. I had similar issue with dashboard - it was flickering due to damaged insulation of the wire. I replaced them with the new set about few months ago and dashboard stopped flickering. But the stereo head unit is still interferes significantly when is closer to the engine bay. Any suggestions?
