Low Battery, Convience Freatures Temporarilly Disabled, After Amp Install??
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2005 E 320
Low Battery, Convience Freatures Temporarilly Disabled, After Amp Install??
I just installed, 2 Diamond D3 Subs in a slot ported box, powered by a D1000.1 amp 1100 watts mono, and a 2 farad capacitor. The Diamond Speakers say 4ohms on them. The problem I'm having is when I listen to my radio for like 10 min or so, I get a message on my dash "Low Battery, Convenience Features disabled" and the subs cut out.
My system was installed by Best Buy, (don't laugh as I was fully ready to pay the stealer-ship whatever it cost to do this but they absolutely wouldn't). The guy at Best Buy couldn't figure what the hell was going on. I called dealership and looked at my manual and the only thing we can figure is when the battery in the trunk gets low, the one under the air filter takes over and the power for the amp is cut off completely. Which doesn't make sense because the aux battery under the hood is supposed to be for the SBC Breaking system.
They tapped into the sub wires on the rear deck to power the amp. I've had no battery issues until this amp install. Am I missing something here, do I need to purchase a new battery? Do I need to pay hundreds for the only pro installer in my town to wire up a simple amp and sub box. Any thoughts would be appreciated! Thanks in advance! 2005 E320 sedan.
My system was installed by Best Buy, (don't laugh as I was fully ready to pay the stealer-ship whatever it cost to do this but they absolutely wouldn't). The guy at Best Buy couldn't figure what the hell was going on. I called dealership and looked at my manual and the only thing we can figure is when the battery in the trunk gets low, the one under the air filter takes over and the power for the amp is cut off completely. Which doesn't make sense because the aux battery under the hood is supposed to be for the SBC Breaking system.
They tapped into the sub wires on the rear deck to power the amp. I've had no battery issues until this amp install. Am I missing something here, do I need to purchase a new battery? Do I need to pay hundreds for the only pro installer in my town to wire up a simple amp and sub box. Any thoughts would be appreciated! Thanks in advance! 2005 E320 sedan.
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From: Tampa, FL
2005 S500 4-Matic, 1978 450SL
I don't deal much with audio system upgrades, but from your description you may need a larger alternator. It would seem that the drain you have placed on the battery exceeds the alternator's ability to charge it.
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From: Arroyo Grande, CA
w205 C63s, w212 E63,w219CLS500-SOLD! w211 E63, 2006 E60 M5 (KABOOM!)
My suggestion would be to measure current draw and voltage loss (at the battery) while your stereo is off and again with it on. I would also measure alternator output to make sure that as skylaw said, your alternator is not able to keep up with the demands. Comparing the information can indicate if you possibly have a weak battery or alternator to begin with and maybe the current being drawn from the amp is just too much for them handle in their current state. If your battery/alternator are 5 years old since you have an 05 vehicle) it could simply mean that it is time to replace your battery and alternator. Hope that helps.
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ML350, Lotus Elise
This is actually a common problem with the W211 E class... The issue is that there is a module at the rear battery that monitors voltage and current draw and protects the system aginst having a high current draw. The problem is that when you play dynamic music the amplifier pulls enough power to drop the voltage momentarily enough to send the car into protect mode.
You are going to need to pull the wiring for the current measuring module and regulate the the sense wire so that it always sees ~13 volts
You are going to need to pull the wiring for the current measuring module and regulate the the sense wire so that it always sees ~13 volts
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2006 E350
Rob, is there anyway you could tell me exactly how to regulate the module? I'm having this exact problem. The battery and alternator are both good so I'm guessing that what you said is my issue. My car audio guy said he would take care of it but needs some more info. Any help would be much appreciated. Thanks.
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ML350, Lotus Elise
Rob, is there anyway you could tell me exactly how to regulate the module? I'm having this exact problem. The battery and alternator are both good so I'm guessing that what you said is my issue. My car audio guy said he would take care of it but needs some more info. Any help would be much appreciated. Thanks.
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Newbie
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2006 E350
Where exactly is the module located? I kinda remember seeing a small black box mounted at the very rear of the trunk but I'm not positive that's it. The way my car audio system is set up makes it hard to see, so before we start taking it all back out of the trunk I wanted to double check. Thanks for the help by the way!
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Newbie
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2006 E350
Well after finally getting the chance to apply the fix it would seem that it wasn't the best solution. The radio no longer shuts off but now I get the "Low Battery, Convenience Features disabled" message all of the time usually when starting the car, which keeps the easy entrance feature from working (the auto up and down for the steering wheel). I did however just put a brand new battery in at the same time so I guess there is the slight chance that it has issues.
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2006 E350
Another question for you Rob, all I had access to was a 6A diode instead of the 5A diode will that make a difference? The electronics store I went too wanted to know voltage and or wattage of the diode they said I wasn't giving them enough information. And also is 100mf the same as a 1/10 capacitor? Again, thanks for the help.
Last edited by jwhbud; Mar 1, 2011 at 04:50 PM.
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From: Chicago, IL
ML350, Lotus Elise
Another question for you Rob, all I had access to was a 6A diode instead of the 5A diode will that make a difference? The electronics store I went too wanted to know voltage and or wattage of the diode they said I wasn't giving them enough information. And also is 100mf the same as a 1/10 capacitor? Again, thanks for the help.
Finally keep in mind that there may be a bit of difference in the values needed for your particular setup. The values i gave worked for a system that i did but yours may pull more current or faster and may require a higher capacitance. The ideal way to do this is to actually put a scope on that sense line so that you can watch it as the music is playing.. The idea is to keep the voltage stable on the line.
Finally you can also try just using the capacitor on the line without the diode.. One issue with the diode is that all diodes have a voltage drop anywhere from 0.7 to 1.5 volts and if the the voltage is dropped too low it can result in the message being present as well.. You ideally want to use a diode with as low as forward voltage drop as possible (0.7v) but if the capacitor works well enough the line may be stable without the diode at all so give that a try...
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From: Blaine, WA
07 E320 Bluetec
One issue with the diode is that all diodes have a voltage drop anywhere from 0.7 to 1.5 volts and if the the voltage is dropped too low it can result in the message being present as well.. You ideally want to use a diode with as low as forward voltage drop as possible (0.7v) but if the capacitor works well enough the line may be stable without the diode at all so give that a try...
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2006 E350
Well after a couple weeks of testing I finally think everything is good to go. I did do what Rob suggested and removed the diode, leaving just the cap, nothing cuts off anymore and no error codes on the dash.
