I have a 2000 Jeep Wrangler Sport and if the head-lights are on and I open a door my player goes off then turns on and I get the battery icon and then the song continues playing. I also get this if I turn my interior light on. As with everyone, I also get the Battery Icon when I start my Jeep if my player has been on. Does anyone know if a capacitor will fix my problem when I open a door when my head-lights are on? Any suggestions would be great.

capacitor ought to help a bit...

i'd also check the battery... and perhaps look into an alternator that can supply the extra amps you obviously need...
--
sancho

In the situation you describe, the capacitor might work, but it would just be a band-aid to cover up a more serious problem. You need to investigate what's going on with your car's electrical system, or what's wrong with the way your stereo and amplifier are wired up.

Please click here for the FAQ entry on this topic.

If I take my Jeep in to the dealer do you know if they can run tests to see if it is a problem with my electrical system?

I've also got a 2001 Wrangler sport (60th anniv) and I have similar issues. I know it's not an incorrect amplifier installation or hookup, as I've done several and rewired mine at least twice. I'm not too sure about the alternator of the wrangler, but I'm betting that it would be pretty stout as aftermarket add-ons are pretty common (winches, fog lights, etc.)

(edit:the stock stats are a 117 amp alternator and a 500 amp battery)

How would the capacitor be installed? Just a decent sized cap just before the 12v+ terminal and gnd? Wired in parallel, like a sound reinforcing cap for sub amps?

Hi all, this is my first post on this message board.
I'm having the same problem on my 94 3000GT. I hooked a volt meter up to the power lead going to the player and had some interesting results:
With the car off, I'm reading 12.3volts. If I turn the dome lamp on or depress the break, the player shuts off momemtarly while the voltage stays a constant 12.3volts. Now if I turn the head lights on the voltage will drop down to 11.8volts, but the player is unaffected. I'm thinking this is amperage issue. I'm going to try tapping into the fues box, or somewhere else to get my switched power. I'll post if it works.

Sounds more like something is wired wrong rather than an amperage issue.

Quote:Sounds more like something is wired wrong rather than an amperage issue

I would think the same thing, (and it may be) but this seems to be a common problem with the 3000gt. The power lead is hooked up to the stock power lead and the ground checks out with the multimeter. I'm by no means an expert, but how would you explain no voltage drop with the player turning off momentaraly? And then reading a voltage drop (with the headlights comming on) and the player stays on. This is way over my head.

I don't know. Perhaps the headlight illumination wire or the cell phone mute wire are connected to something they should not be connected to. Something strange like that.

HI!
A capacitor will not help your problem in this case. I say this because your problem is due to CONSISTENT low voltage. If your headlights are on, you are continuously drawing the voltage down. A capacitor will only store current to supply the voltage for a short period of time. Also, power flows in more than one direction. The capacitor would be supplying current to your headlights, until it reaches the voltage that the system would initially be at without the capacitor.

To fix even that problem, you'd have to install a diode to the supply wire for the capacitor, this way the current wouldn't flow backwards into any other devices.

And, with that done, your capacitor would have to be of significant size, say 1 Farad, to supply your Empeg with enough voltage for more than a few seconds.

A fairly costly issue. Maybe your Ground, and your 12V supply should be connected directly to the battery with, say, 12 gauge wire to minimize voltage drop. This could make a big differencre. But watch out for ground loops, you'd have to run the ground for your deck and amps to the same point to eliminate alternator whine.

Hope this helps clarify capacitors a little!??

From what I have seen on my empeg, it's fairly sensitive to transients. i.e. when a heavy load is switched on the negative going spike on the supply causes it to think the supply is going down. No problem with the engine running but running off battery only and I sometimes have this problem. A cap should fix this. Silkysmooth is correct in saying that if the voltage is continuously low then you have other problems. From memory the empeg switch off voltage is around 8.5 volts. If your system is getting that low then you have greater problems.

A possible other fix would be to provide a small amount of averaging on the low voltage input detection circuit. I'm guessing that as soon as it goes low for one sample the player will restart. If the empeg say checked for 10ms of continuous low voltage and [u]then[/u] shutdown, a lot a the problems might go away. Can someone who knows the hardware comment on this? It might even be possible in Hijack if the sampling is done in kernel space

We had similar problems with ESD testing on a project here at work and this sort of averaging fixed the problem quite well.

If the empeg say checked for 10ms of continuous low voltage and [u]then[/u] shutdown, a lot a the problems might go away.

It's gotta do the flash write ASAP, so it can't afford to wait.

I understand the flash save problem. We have exactly the same issue with our products. We need to save to flash once we detect a power off although we actually have an supply value rather than a simple binary good/bad indicator. I don't know the timing constraints on the empeg but I'm sure a small delay (OK maybe not 10ms) won't cause too many problems.

Hi.

It might also help to write the flash immediately, but not to power off after that, but to check for low voltage again.
Also: Why does the empeg shut itself down on low voltage? Saving the flash immediately is correct behaviour, but why the complete shutdown? If the power supply comes up again while writing the flash, the empeg could simply continue running. If the power doesn't come up again, the lack of power supply will shut the empeg down automatically, so why bother?

cu,
sven

I'd actually forgotten about that idea, Sven.

We do that too in our product. We shutdown and then if the power comes good we don't do a full restart. Doesn't happen real often though.

In our case if power is gone long enough to cause the shutdown, then it's a pretty fair chance it will go for long enough for us to die completely (We make 3 phase electrical energy meters)

We don't shut down on low voltage; on low voltage we blank the screen (turns the amps off and helps reduce pops if the unit is actually being pulled out of the car without powering off) and save to flash.

The player continues running, and if power hasn't actually gone away, it will re-enable the amps and screen & show the battery icon.

The only time the player actually *reboots* is if the voltage gets so low that the 3.3v PSU drops out and the reset chip (which monitors the 3.3v rail) will then reset the CPU after the PSU becomes stable again.

ISTR this isn't until something like 6v on the mk2. The battery symbol comes up at around 10v.

Hugo

I messed a little bit with the jeep and my problems only occur when the interior dome light comes on. I pulled the light and just the under-dash lights don't cause the player to shut-down.

I can't recall if it comes back on shortly after the light is turned on, which would indicate a short voltage drop (negative spike), or a longer one. A longer one would probably indicate that they are pulling from the same source wire, and it could be overloading the current draw from the single source.

I'll meses with addding another power feed from the battery (fused of course). 12 gauge? I've run amps on smaller. I was thinking 16 and maybe 14, if I can find some.

my problems only occur when the interior dome light comes on.

I dunno... I can't help thinking that if turning on a single three or four watt light bulb takes your whole electrical system down enough to crash your empeg, then you must have some other problems going on.

And why would you try to "economize" by using the smallest wire possible to feed the empeg? Sure, it might run OK on 16 gage wire, but why take the chance?

tanstaafl.

altman said the "reboot" voltage is something ridiculously low like 6V, but what exactly is the "noncritical" voltage cut off limit, ie, the limit for the unit switching off the screen/saving to flash but NOT rebooting entirely? it must be pretty high - id estimate 10.5 to 11v? i have a pretty good spiral cell battery in my car and the audio system of course has its own 4ga feed directly from the battery - power to my empeg is branched off this feed - so no mucking about with the car's factory supply. i dont get any problems with lights coming on and off, or doors opening etc - but starting the car will cause the battery icon to come up, and stay up for another4 seconds or so, but of course the car's voltage probably DOES drop below 11v when youre cranking anyway. (however my old JVC deck seemed to stay on and play without being interrupted no matter if i was in the middle of starting the car or not - too bad the empeg is not like this! understandably tho the empeg has got a lot more sensitive components onboard)

it just may be that the dome light and the feed to the empeg (in the case of the jeep owners) may be on the same feed? in my car, the original headunit power feed was also tied into the cigarette lighter, ie shorting that out also killed the HU power. so, perhaps the dome light (surely it is more than 5w) coming on, is enough to momentarily drop voltage below the "noncritical" standby cutoff voltage hence turning your empeg seemingly off, then on again, with battery icon. is your dome light also connected to additional courtesy illumination lights in the doors as well? that all light up when you open the door? it might all add up to a large momentary drop in voltage...?)

the problem(?) just seems that this 'noncritical' cutoff voltage on the empeg is pretty high... so it doesnt take too much of a drop, to make it panic and blank out.

a seperate situation can be seen at home - here in NZ the home power voltage is 220/240v, which rendered my 120v AC adaptor that came with the empeg, rather useless. i forget how many amps the factory adaptor is now, but im sure it was over an amp. 1.2amps? standard adapters for running powered speakers, and walkmans, and that sorta thing, normally are built to provide about 500mA. with just the one 10gb HDD in the system, running on a 800mA adapter that i dug up, the unit was having troubles running - it would boot up, and sit fine, but any HDD activity (eg, uploading a song) would blank the screen and then come back up again, as altman stated, "The player continues running, and if power hasn't actually gone away, it will re-enable the amps and screen & show the battery icon." which is exactly what happens. i assume the current (amperage) draw was large enough to cause a corresponding drop in voltage which then made the unit blank off, then come back again.

i changed to a large benchtop power supply, that does 12V at 5A, and it now is fine.

id really have to say that a capacitor/diode solution may be whats needed to stabilise the voltage, when those lights are coming on and off - it only needs to smooth the voltage for a split second, so maybe something as large as 1F may not be necessary, but you can only try smaller values and work up from there? maybe a 12V 0.2F to begin with... those are still pretty large tho.

ok i'll stop now.

Correct, the noncritical cutoff voltage is about 10v, as Hugo said. I think this is in the FAQ.

Correct, if one is having trouble with interior accessories competing for the player's juice, the next thing to try is to wire the player directly to the battery to see if the problem goes away. I think this is also in the FAQ.

Correct, most cars' voltage will drop during/after cranking and the battery icon during this stage is normal and nothing to be worried about. I think this is also in the FAQ.

Correct, adding a capacitor to cover up the occasional dips in voltage will solve the problem, however one should not need to do so in a properly wired system. The only thing that one might have to resort to is a capacitor for is to cover the cranking period if it's a problem.

When starting my car, I have the same battery issue most times. Also remember that when starting most cars, the accessories line will be disconnected (among other things) to ensure as much power is available as possible. I don't think a 1 or 2 second pulse on the switched line causes the battery icon to appear though it might make it blank the screen. At least that's what I see. It can be kinda annoying because it blanks the screen just as my animation is going.

I'm in Australia and had the same plugpack problem. If you're in NZ try Jaycar for a MP3137. A$32.95 for a 12V 1A switchmode which works flawlessly with my empeg with 1 30G drive. I originally tried a crappy Dick Smith 12V 1A unregulated thing and it wouldn't cut the mustard. The Jaycar is also quite light and compact (being switchmode) compared to the DS one. And would beat carrying a bench supply around too if you want to use your empeg at a friends house or something like that

the FAQ entry on the "battery icon" description is pretty thorough but i guess each of the symptoms/factors mentioned *could* have a bit more detail added. but yes its mostly there i did not see the part about alternate wiring direct to the battery - in my eyes coming from a DIY car audio background this is always a method of troubleshoooting but some others may not like it as it may seem a bit of a brute force method the jeep/other owners might want to consider this as hopefully it narrows your problem search down, and also hopefully allieviates extra headaches!

thank you shonky for the details on the adapters. i was wondering tho... current draw as listed on the lables of both HDD's in my empeg are about 550mA each. so both, if working, could peak past 1.1A, and thats not considering what the empeg base draws as well. what are the other 120gb users using? perhaps one of those Infinite Power Generators that were on sale at thinkgeek.com for $99. what a great idea!

Yes but that's at 5V. 5V at 550mA is 2.75W. Times 2 is 5.5 watts. 12V at 1A is 12W. With switching supplies getting up around 70-80% efficient, you easily get 10W from your 12W supply.

If you were using linear regulators and running 5V at 1A from a 12V supply you'd be dissipating (wasting and turning into heat) about 7W.

i did not see the part about alternate wiring direct to the battery

Going and looking at it, I see that I only say something about how the wiring to the player could be inadequate, and I don't come out and say to wire it right to the battery. And the truth is that for most cars, you shouldn't need to wire it right to the battery. The factory radio wires should be enough in many cases. But I'll see if I can beef it up.

Problem solved! Well sort of. I have found that my memory output (car source) was some how causing the unit to shut off of a half second when I would step on the brake or open my door. I guess the memory input is just as important as the ignition. sense. input. If both leads are not good quality pwr source, then you'll have problems. For now I'm just running ign. sense and memory together until I can find another source for my memory. I may just run a lead to the battery. The only problem I have with running both wires together is the player shuts off suddenly and I get a pop through the amp. But it's better than the player shutting off every time some one gets in the car or I step on the brakes.

Problem solved! Well sort of. I have found that my memory output (car source) was some how causing the unit to shut off of a half second when I would step on the brake or open my door. I guess the memory input is just as important as the ignition. sense. input. If both leads are not good quality pwr source, then you'll have problems. For now I'm just running ign. sense and memory together until I can find another source for my memory. I may just run a lead to the battery. The only problem I have with running both wires together is the player shuts off suddenly and I get a pop through the amp when I turn the ign key off. But it's better than the player shutting off every time some one gets in the car or I step on the brakes.

Memory actually isn't only memory - it's also main power. The switched +12V lead is just a signal to turn on/off (at least for MkIIa's - on earlier models power could be cross-fed)

If you go with a new wire from the battery - don't forget to fuse the wire close to the battery!

/Michael