radio hell... thoughts..
Thread Starter
Le Mans Master
Joined: Jul 2003
Posts: 7,501
Likes: 1
From: Maine
radio hell... thoughts..
ok.. pioneer head unit, 5 1/2" in the kick panels, 6x9 in the rear and a 12" sub with an amp... everything is new... even the wiring... the stereo cuts in and out.. not all the time , only when the car is running... i was having this same issue and could not track it down... i replaced the whole set up and new wiring.. same issue.. everything is wired right.. it sounds perfect when the car it off... but when its running its cutting out volume makes no difference... 
Team Owner
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From: Western NY
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Joined: Feb 2000
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From: Hebron IN
If it sounds fine with the car off, I doubt the problem is a weak alternator. Shutting the car off after a long drive, the battery would be partially drained and your problem would still the there...most likely worse. You'd also have slow/no starting and dim lights while driving.
The regulator in the alternator may be bad causing an over voltage issue which causes the head unit or amp to shut down on internal protection.
What voltage do you have at the stereo and amp with the car running?
The regulator in the alternator may be bad causing an over voltage issue which causes the head unit or amp to shut down on internal protection.
What voltage do you have at the stereo and amp with the car running?
Burning Brakes
Joined: Mar 2012
Posts: 1,200
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From: Belle River Ontario
2015 C3 of Year Finalist
I'd honestly start with re checking your wiring.
Sounds like the radio is fine while siting still, moving ...it's cutting in and out which if it's a CD I can see it skipping , other than that it sounds like a short in a wire somewhere to me.
Good luck.
Sounds like the radio is fine while siting still, moving ...it's cutting in and out which if it's a CD I can see it skipping , other than that it sounds like a short in a wire somewhere to me.
Good luck.
Team Owner
Joined: Jan 2006
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From: Crossville TN
Very simple. The amp doesn't have enough capacity to supply the speakers. What does it sound like when you have the volume down low?
If it still has the same problem, the amp is defective.
If it still has the same problem, the amp is defective.
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Joined: Mar 2012
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From: Carol Stream IL
I also think it is the alternator not being able supply enough juice. YOu should also consider how many peak watts are being drawn by the amp and anything else that is on that circuit. Then you should make sure the power supply wire is big enough to safely carry that current w/o over heating. I don't have the maximum current numbers handy but you can find them in Mark's Handbook for Mechanical Engineers.
Pro
Joined: Mar 2012
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From: Carol Stream IL
Also, if the amp is cutting out on big bass notes, then you need more capacitor. The capacitor serves to keeps the voltage more constant. A big amp will draw a lot of power on heavy bass notes and cause the voltage to drop on that circuit. If the voltage drops, the current must also drop because the two are directly related and the impedance of the speaker is fixed. current = voltage / impedance.
This capacitor should be wired between the amp power lead and ground.
This capacitor should be wired between the amp power lead and ground.
Burning Brakes
Joined: Mar 2010
Posts: 943
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From: Valdosta Georgia
Check your grounds at the head unit and the amp. When you say it cuts out when the engine is running, does that mean just the sound, or the whole unit powers off? Is it a removable face plate? How much vibration is there when the motor is running? It sounds to me like whatever ground you are using at either the head unit or the amp is intermittent.
What all is the amp powering? If it is just powering the sub, the cap will be a good purchase, but I don't think it will solve the problem, because if the amp is just powering the sub, you should still have sound at the full range speakers. I think what you are saying is you lose power to the head unit, so I'd start there. Run a good known ground to the head unit first, I'd run a dedicated ground if you haven't already. You said you were having the same issue with your old radio, so I'm really thinking its a ground issue.
What all is the amp powering? If it is just powering the sub, the cap will be a good purchase, but I don't think it will solve the problem, because if the amp is just powering the sub, you should still have sound at the full range speakers. I think what you are saying is you lose power to the head unit, so I'd start there. Run a good known ground to the head unit first, I'd run a dedicated ground if you haven't already. You said you were having the same issue with your old radio, so I'm really thinking its a ground issue.
Last edited by Drawmain; Jul 11, 2012 at 11:57 AM. Reason: more thinkin
Team Owner
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From: Crossville TN
Re-read post #8. If you turn the volume down low and the system works fine, then your amp can't supply enough power to the speakers or the alternator can't supply enough current to the amp when the volume is increased.
If the unit still cuts-out at low volume, your amp is defective.
If the unit still cuts-out at low volume, your amp is defective.
Thread Starter
Le Mans Master
Joined: Jul 2003
Posts: 7,501
Likes: 1
From: Maine
Re-read post #8. If you turn the volume down low and the system works fine, then your amp can't supply enough power to the speakers or the alternator can't supply enough current to the amp when the volume is increased.
If the unit still cuts-out at low volume, your amp is defective.
If the unit still cuts-out at low volume, your amp is defective.
Burning Brakes
Joined: Mar 2010
Posts: 943
Likes: 15
From: Valdosta Georgia
Okay, that narrows it down to the head unit for sure then. Two things to check, one, the ground I mentioned earlier, and two, the antenna lead. I had a truck once that the radio would cut out if the antenna lead was loose, not sure if the pioneer is like that, but it sounds like the vibrations of the motor are enough to shake something loose. Start with running a dedicated ground, then move to the antenna lead if the first one doesn't fix it.