Why does my stereo cut out only when engine is running?

korygrandy

Senior Chief Petty Officer
Joined
Apr 14, 2010
Messages
698
Okay, I'm working on upgrading my stereo and am running into issues.

I will start by describing the system and wiring.

Marine Receiver - Kenwood KMR-330
Marine Amp - Clarion APX490M
Marine Speakers - Polk Audio BB651 (2 in front) / Infinity 6912M (2 in rear)
Everstart Cranking battery (2 years old)
Everstart Marine Deep Cycle (brand new)

Amp pos and neg is wired directly to battery via 12' 4gauge wires, 1 for positive with a 60amp in-line fuse and 1 for negative. The remote turn-on is wired to the reciever's remote turn on wire.

The receiver Ignition Wire (red wire) is wired by itself directly to my ACC switch, my battery wire (yellow wire) is wired to the fuse panel on the same 30amp fuse my depth finder is wired to and the receiver is grounded to the same bolt my horn is grounded to.

When the engine is running the receiver will cut out roughly 2 to 3x a song(along with the amp since it's connected to the receiver via the remote turn-on).

Now to make things more confusing if I connect the boats original positive and negative wiring to the everstart cranking battery, and only the amp to the deepcycle the amp will not power on.

My hopes are to use a VSR to isolate the starting battery and the deep cycle so I won't get caught with a dead starting battery.

Any suggestions as to why this everything works as expected without the engine running but cuts out when the engine is running and why can't I hook the amp up by itself to the deep cycle?
 

RickJ6956

Petty Officer 1st Class
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Jul 18, 2009
Messages
349
Re: Why does my stereo cut out only when engine is running?

When you installed the new battery did you connect its negative to the original battery? (That's the way it should be.)
 

korygrandy

Senior Chief Petty Officer
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Apr 14, 2010
Messages
698
Re: Why does my stereo cut out only when engine is running?

Doh. I will do that. This still doesn't explain why the radio is cutting out in a 1 battery situation.
 

RickJ6956

Petty Officer 1st Class
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Jul 18, 2009
Messages
349
Re: Why does my stereo cut out only when engine is running?

I suspect that wiring everything correctly will fix that problem. All kinds of strange things can happen with loose or improper wiring to negative/ground. The radio may be shutting off to protect itself from damage.

As for the other issue, it is again related to the negative wiring. The amp's remote turn-on is wired to the receiver which is on Battery #1 and the amp is on Battery #2. Because there is no common negative, the remote can never complete the circuit through the amp's turn-on relay or sensor.
 

scipper77

Commander
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Sep 30, 2008
Messages
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Re: Why does my stereo cut out only when engine is running?

Could it be as simple as high alternator output. Maybe the electronics are getting too much power when the alternator is running.

Also, I've generally only seen amps and receivers cut out like this when they are trying to put out too much power (like if you put low impedance speakers to them). Maybe the protection circuitry acts differently based on input voltage.

Does it only cut out at high volume?
 

korygrandy

Senior Chief Petty Officer
Joined
Apr 14, 2010
Messages
698
Re: Why does my stereo cut out only when engine is running?

Yes it does cut out at high volume. I am going to try a few things...add a VSR to the dual battery setup and see if it still cuts off and back on at high volume with the engine running.
 

scipper77

Commander
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Sep 30, 2008
Messages
2,106
Re: Why does my stereo cut out only when engine is running?

Try disconnecting the speakers one at a time to see if you have a bad speaker drawing too much load. Does the amp have an led display that gives an error code when it clips? is the amp or receiver overheating?
 

blairjbyrd

Petty Officer 2nd Class
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Jul 11, 2009
Messages
109
Re: Why does my stereo cut out only when engine is running?

make sure your speaker wires from the amp are hooked correctly. What i mean is make sure the pos wire is connected to the pos on the speaker as well as the neg wire. make sure there is no frayed speaker wire touching metal on the amp also. Try that I had this problem on my home theater system.
 

korygrandy

Senior Chief Petty Officer
Joined
Apr 14, 2010
Messages
698
Re: Why does my stereo cut out only when engine is running?

I know the fronts are wired properly as the speaker terminals are labeled but the rears not the case. I am going to take a look and see if the thicker terminal is the positive on the front and if so assume it is the same for the rear speakers.
 

korygrandy

Senior Chief Petty Officer
Joined
Apr 14, 2010
Messages
698
Re: Why does my stereo cut out only when engine is running?

Aha! I got it. Don't ground stereo's to random bolts...it doesn't work. I grounded it straight to the fuse block and it works perfectly now! Thanks for everyone's input.
 

scipper77

Commander
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Sep 30, 2008
Messages
2,106
Re: Why does my stereo cut out only when engine is running?

Glad you got it. Remember, boats don't have frames that can be used as a ground like a car. You have to use the negative terminal of the battery or something tied to it.

Now don't take this the wrong way but be responsible with the volume level of your music. Noise pollution is really inconsiderate and sound travels quite a ways over the water because there are zero obstructions like trees or buildings to damper the sound.
 

timlange1

Recruit
Joined
Jul 11, 2014
Messages
2
I had the same thing happen to me when I replaced my radio. You need to use a resistor spark-plug. They can range anywhere from $8.00 to $20.00 dollars. Mine cost $10.99. I have a mercury 50hp standard gear case 2007. The spark plug I used was NKG BPZ8H-N-10. You need to make sure the Z is on the plug or it will just be a standard spark plug. I don't know how many different engine types this will work on but I'm sure there is a resistor plug for almost all engine types.
 

timlange1

Recruit
Joined
Jul 11, 2014
Messages
2
I had the same thing happen to me when I replaced my radio. You need to use a resistor spark-plug. They can range anywhere from $8.00 to $20.00 dollars. Mine cost $10.99. I have a mercury 50hp standard gear case 2007. The spark plug I used was NKG BPZ8H-N-10. You need to make sure the Z is on the plug or it will just be a standard spark plug. I don't know how many different engine types this will work on but I'm sure there is a resistor plug for almost all engine types.
 
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