[laserguy]

I came across this thread. Basically says, Honda will not supply the full 14.4 plus volts for longer periods of time.

It applies to all Civics and Accords even from the mid 90's, I found other info indicating minivans being affected, I would not be surprised if the Ridgeline is affected also.

These kills the batteries faster, when running audio systems with a potential of over 1K watts of power. The report I read on line on different forums is the ELD or the ECM does not know the extra power being used for the amplifiers and the ELD not allowing the alternator to cycle longer periods of time while driving.

Since Civics have 90 amp alternators these suffer the most with people planning to power an audio system with over 1000 watts, having to replace the alternator and a bigger battery, when many other cars that do not have this ELD system HOnda uses, do not have issues killing batteries or needing better bigger alternators or batteries, running lots of power for the audio systems.

This issue can be tested easy I assume playing music (maybe powering a whole system with at least 500 Watts) and just watching when the voltage drops below 12.6 and and alternator kicks in, cycling between battery only power, alt and battery power to go back to 14 volts or more and dropping back when it should not.

Bypassing the ELD will keep that short cycle from happening many times that reduces the the batteries and alternator's life, running the alt for longer periods of time is not bad for the battery or alternator, the many short cycles is what affects both, according to what I read.

I am not a mechanic or know car electricals, not 100% that it is the issue with the trucks, not having 14 plus volts the majority of time while driving, limits potential maximum power from Car Amplifiers since most deliver over 20%, maybe up to 50% more power at 14.4 volts than at 12.6 volts.

If anyone is interested in searching this issue, test it and report it, please share your findings here on this thread. Even without using 1000 Watts, maybe this is the reason the batteries die sooner that expected. Honda uses this system to save gas, not sure the fraction of savings is worth it, maybe having an extra 3-4 years of battery life is better than an fraction of mile per gallon savings.

Some companies sell upgraded alternators that include the kit to bypass the ELD for Civics. Simpler but costly, no clue if the kits are availble for sale separate. I would not feel too confident making my own like shown on the thread below.


http://www.stevemeadedesigns.com/board/topic/139844-how-to-eld-bypass-for-honda-civicaccordfit/

 

[OhSix]

Couple of thoughts on this topic:

As government increases pressure on fuel economy requirements, minimizing rotational resistance of external components hung on engines is the focus of every auto OEM. Since dropping alternator output below maximum output = less drag, it makes perfect sense Honda would devise this method to incrementally increase MPG, especially across the fleet.

The alternator is never *off*, rather, its magnetic field is adjusted by the ECM so that output maintains a minimum level of 12.XV at the battery. When the battery dips below that minimum as sensed the ELD module, ECM adjusts the alternators field to deliver higher V to the battery. For the purpose maximizing wet cell/lead acid battery life, minimizing alternator load and reducing engine drag, ELD is theoretically ideal because: A) the battery is never allowed to sulfate by dipping below 11V and; B) Alternator output is electronically adjusted which *may* extend the life of charge circuitry. I haven't seen information about the granularity of those adjustments but I doubt they are binary (full high/full low).

Enthusiasts seeking to squeeze every penny out of dollars invested in monster amps have concocted a way to bypass the ELD effectively tricking the ECM into adjusting the alternators magnetic field to max_at_all_times. It's understandable they look for return on investment in audio, but a couple of things come to mind:

Only sustained demand exceeding battery capacity would cause the battery to prematurely fail, and it takes repeated dips below “dead” (about 10.5V) to negatively impact an otherwise healthy battery. Although it might be possible for a listener to damage a battery by repeatedly exceeding charge system capacity, it makes me wonder about the aural health of someone doing such a thing.

Even if it’s true an amplifiers rated output drops in half @ 12V vs 14V, the acoustic delta is only 3db. 3db is barely audible in terms of SPL. The sonic attribute most likely affected by a 3db reduction of output is dynamic range (or headroom) which is not going sour anyones listening experience @ freeway speeds.

Modifying the factory battery management system has the clear potential to overcharge the battery and will definitely shorten cell life. Doing that for the potential to gain a nearly imperceptible SPL increase comes with plenty of risk.

 

[zroger73]

Or, one could simply NOT install an over-powered audio system and have the following advantages:

1. The charging system works as designed.
2. The driver and passengers won't go deaf as quickly.
3. Those outside the vehicle can live their lives in peace without this additional source of noise pollution.

 

[OhSix]

Or, one could simply NOT install an over-powered audio system and have the following advantages:

1. The charging system works as designed.
2. The driver and passengers won't go deaf as quickly.
3. Those outside the vehicle can live their lives in peace without this additional source of noise pollution.

Well, there is that option.

 

[laserguy]

Although it is not worth to install any bypass. Since it may void warranties or decrease resale value, assuming they find out, I would not shy way from getting amplifiers with enough power to have the extra headroom since most likely not even close to 600 watts will be used in a real environment, and that is more than enough for a good SQ system to offset any potential minimal power loss caused by the ELD, ECM.


Only

Smaller, lower powered amplifiers may need that extra edge depending on the user and his or her needs. That can be easily fixed by getting a more powerful amplifier.

And Monster amplifiers seeking higher SPL levels will be affected by having to replace batteries or alternators and maybe having to worry about that bypass option to avoid other expenses associated with it.

 

[OhSix]

And then there's the small issue that the only accessory one could install that needs 14V to perform as advertised is certain power amplifiers. This "fix" is pretty extreme in that regard.

 

[laserguy]

I thought I would transfer some of my posts related to this topic, and posts with great contribution from ohsix, on tests with advanced tools and related data.

The original post on this thread has a link, on how to bypass the ELD when the owner needs to, it may apply more to guys seeking High SPL sound levels.
On post 4 on that thread there is an updated information reagarding how to bypass the ELD with the Ridgeline. Personally I would not do it, since I'm not about SPL, perhaps some interested in SPL may want to try the mod to benefit to stay above 14 V. On another note, it seems that in SPL comps, they allow the engine on and personally I have not noticed a lower reading than 14.xx volts while the shifter is on park with engine on and the blower motor on. No clue if civics or accords behave the same way or not and they all want to bypass the ELD.

Basically what happened was that I noticed very low peaks of 12.5 V voltage, I thought it was related to the aftermarket multi amp sound system used at high volumes. Later I discovered that it was not related to the sound system but simply to the Honda charging system, and since we all keep the air blower motor on, the voltage remains close to 14V most but not 100% of the time, making it hard to notice in city driving, and staying at 12.6V most of the time if the air blower motor was off.

Later when driving on the highway, with the air blower off or any accessory except the head unit and amplifiers, I noticed above 60 mph the voltage stayed above or closer to 14 Volts and as soon as the speed dropped below 60mph the voltage dropped and stayed at 12.5-12.6 volts even with th music on but not at maximum volume levels.

Thanks to ohsix for taking the time to perform some tests with advanced tools to confirm this behavior on our trucks. Note that Newer models may or may not behave the same way as the older models.

Here are some of the posts related to the topic

Many links found with what appears to be a normal thing for Honda's, to apparently save gas and extend alternator and battery life.
Some threads got in different directions or some did not want to accept it was normal, leading to multiple alternator and battery replacements.

It makes sense, to have some voltage fluctuation as long as it does not drop below 12 or go above 15 V it would be fine, my range has been 12.5 to 14.7 volt, one time max.


A little confirmation will be appreciated but not needed. Time will tell and I'll keep my eyes open unusual changes


Voltage question...is it supposed to fluctuate while driving? - Honda Prelude Forum


Fluctuating voltage normal? | Automotive General Topics | Bob Is The Oil Guy




Battery voltage drops to 12.5 after driving for a little bit. - Honda-Tech




Random voltage drops? - 8th Generation Honda Civic Forum

Laserguy, your observations made me curious. Mostly because I have a dedicated voltage gauge and dual port USB adapter with a built in meter - like I think you have.

View attachment 249762

Using those as reference, I'd never observed voltage drop to anytime below 13.8, remaining @ 14.1 or 14.2 90% of the time, regardless of RPM. Then I tried your example of no interior accessories engaged. And sure enough, I saw variations. Turns out, I never drive anywhere without interior fans running, so that explains why variations hadn't been noticed.

So I got the idea to log and graph OBD voltage with the Torque app. Looky here.

Top graph is a quick trip to the store late this afternoon - no interior accessories engaged. Bottom graph is the return trip, interior fans on, occasionally engaging AC.
View attachment 249746

Raw data is also attached.

View attachment 249754

Couple of quick notes.

With accessories engaged (such as interior fans, AC, engine/AC cooling fans, MAX_Variation is .3V, regardless of load. 13.0 to 13.3. That's pretty tight regulation.

When accessories are OFF, MAX_Variation = 1.9V, 11.5 to 13.4. I *think* the peak V was reached as engine cooling fans engage under thermistor control.

Oddly, the built in & USB gauge read 1V higher than ODB power. I know those gauges are accurate because they was tested against a lab grade variable power supply, the USB gauge consistently reading .1 lower than the built in gauge.

The only explanation I can come up with is where they connect in the DC supply system. Curious, I've poked around the FSM and didn't immediately find termination points for the circuit powering the console accessory ports or OBD (PCM) connector. Which pisses me off, so I'm gonna find it. Just not tonight.

Thought you might want to pass along these measured results.

Yesterday was mild during the drive home, so I made a point of leaving all accessories off while logging data via Torque during the 30 minutes ride.

Observations:
- At start up, alternator output is high.
- With accessories off, alternator output "cycles low" 2 minutes after start up.
- During normal drive, at all speeds under 60 MPH, alternator output cycles high to low in two minute intervals.
- Alternator cycle high can be invoked by load. Power windows up/down. Interior fan ON. Parking lights ON.
- Any load greater than brake lights causes alternator to cycle high.
- When alternator is in "low state", loading the system causes "high", removing the load causes near instant return to "low".
- *It appears* "low" = battery is NOT receiving voltage from alternator. Logic: when in low state, voltage continues dropping to a minimum threshold where "high" state "tops off" the battery. Hence: low/high 2 minute cycle intervals.- At speeds above 60.5 MPH, alternator remains fully engaged, charging batt at all times until speed is reduced to 59MPH when it returns to "low".

Using data logged last night, isolating speed in relation to OBD voltage, note this chart. At speeds above 61MPH, alternator is "high" at all times.

Below 60MPH, alternator cycles in out out of "low" & "high" states.

View attachment 249922

I'm fascinated by this behavior. And *think* it makes sense that when "low", the alternator is actually "out of the circuit", not charging the battery at all. Unless an accessory is engaged, the battery runs PCM and such until a min_threshold is reached, at which time alternator "reconnects" to the circuit, bringing the batt up to an acceptable (yet to be known) level, then cycling out again.

Which supports what others said in the links you provided - which is - Honda unloads the alternator as a fuel eco move. As incredibly small as that might be, it makes enough difference in their fleet numbers to be worth the NRE invested in development.

At all speeds, alternator is "in circuit" when current above PCM requirements is needed. In my case, I never noticed cyclical behavior because fans were always on.

Man! I love learning new stuff.

 

[laserguy]

Well! One of the many questions that come to my mind about the Honda charging system is:

Honda by investing a couple of dollars in electronic parts and the charging system, not only do they look good for saving gas and alternator wear, I'm not so sure about battery life and my question is right below.

One thing is,keeping the voltage above 14 V most of the time will reduce the alternator life, and boil the fluid in the battery reducing it's life, SPL guys don't care I guess since every Db and more power counts even if they have to replace batteries and alternators every 18 months.


Mmm
Does Honda save millions by getting away assuming the system helps, to get away buying lower cost batteries with low cranking amps and very tiny batteries in most if not all vehicles?

 

[Carsmak]

Interesting thread, I'm with Z, on the "Monster systems", but interesting none the less.

 

[OhSix]

Couple of Sunday morning thoughts on the concept of "needing" to by pass Honda's load detection circuit:

First is: The premise is erroneous. The post linked to Steve Meade Designs overlooks the simple fact that if <14VDC is "needed", "low alternator" function can be defeated by simply leaving interior blower motor on @ low speed. All voltage/current available in an unaltered DC power system is now available to the audio system by use of a switch and circuit control method that's already right there. No hacking into factory wiring is required. Problem solved.

Second is: The premise is that to achieve rated output, amplifiers require 14VDC. What happens when less than 14V is available? Less current at the output terminals = reduced acoustic output. Hence, the perceived "need" to by-pass ELD is focused on a premise that more is better. I've not bothered to look into the output deltas between audio amps limited to 12V vs having 14V available because I don't really care. For me, eeking out the drop of power is a dragon chase I don't care to participate in.

Generally speaking incremental increases in power output are meaningless to the sonic landscape projected by a given system. Without getting into the LONG history of human hearing sensitivity, suffice to say that each 3db increase in acoustic output of a system - no matter what kind or where it is installed - requires doubling the number of watts from the amp(s). Ponder that for a moment. To make even the smallest audible difference in a 500W sub amp, you'd need to step up to 1KW.

Can your ear hear a 3db increase? Therein lies a great never ending debate - the real answer is yes and no. It has been proven, over and over and over again through lengthy lab, listening and blind testing that the perceived benefits of the "3db delta" is subjective at best, and real world listening tests are inconclusive. The issue might be best compared this way: two identical cars, configured exactly the same. Both measured on a dyno. One measures 200HP at the drive wheels, the other 215HP. Can you feel the difference in your butt dyno? If those vehicles ran 25 back to back 1/8th mile drag races, would 215HP stomp the 200HP every time?

In the context of a DC powered audio system, a healthy supply is always a good thing, but volts and current are whats needed for sustained and impulse output in any audio system.

If someone is interested in getting the absolute best out of a system and has unlimited funds, the worlds shiniest hot rod sporting the most outrageous audio system can be built. Your mind can be blown by chrome and billet, wires and connectors, amps and speakers, time aligned this and that, but down here in the real world where drivers live and work, we want to enjoy our rides and get the best bang for the buck. This hair splitting stuff often leaves reason in the weeds. 2KW vs 1KW system. Cost, current demands on the supply system, space requirements, ETC, all for a 3db increase that may or may not be heard - but hey, bragging rights are worth the effort and expense, eh?

I'm one who scoffs @ the on going discussions around 14V mobile power supply systems requiring dedicated, secondary alternators and battery system. It's pure absurdity IMO.

Want the best DC system for your system? Audio nuts would do well to invest in deep cycle batteries connected to the the starting battery via an isolator. Most use cases wouldn't require beefing up the alternator either - although thats probably a good idea. By having a dedicated supply for the amps, impulse voltage and current is retained, the OEM charge system remains unaltered & starting battery life is maximized. While the RL is challenging for big audio in the cabin, the trunk is a prime spot for a mondo batt system. IMO: that's where power seekers should focus attention.

As far as "monster systems" go, quality (timbre, nuance, color, tone, flavor) vs. quantity (neighborhood disturbing SPL) are two very different things. IMO: the factory DC system is plenty good for powering a fine audio system. It would probably do OK for SPL freaks too - but the RL ain't real friendly to those guys unless they are willing to loose the back seat.

There's something about the car hobby that drives reason (at least my version of reason) out of the conversation. Saying it again: don't worry about iddy biddy incremental things that make little difference. Make informed decisions about every component in a system within your budget, keep the DC system healthy but don't alter circuits known to be reliable over millions of collective miles, be mindful of installation details, relax and enjoy the ride.

 

[laserguy]

I Totally agree with the previous post from ohsix.


Maybe the charging system functions Just like some battery smart chargers, once a full charge is reached, it keeps it around 12.7 volts when no big load or additional accessory is on, it's not a bad thing.

The only concern is driving basically with battery power even if being regulated or kept at that level with the charging system.

Also while having the radio on, no accessories or blower motor on, 2 amplifiers on at above average volume, it did not seem to change or affect the behavior like if they were not part of the current consumption or use.

It's good either because the class D amps are efficient, or the charging system can handle it. No signs of lack of power or anything yet. And even if there was signs of some power failure, I would not pass the ELD, when I can keep the blower motor on, while driving.

Time will tell, I'll pay more attention. Having a 130 amp alternator may be the difference with the Ridgeline charging system, since some civics come 80 amp alternators, that combined with ground cables thinner than the main power wire going to the alternator, that simply makes a good cobination for failure with a sound system capabable of 800W or more and needing to bypass the ELD and probably having to abuse or push the limits of the alternator to keep the voltage high, just to avoid, dimming lights, amplifiers going in to protect mode once voltage drops below 12 volts for a significant period of time.


carsmak, asked on the other thread. Why 60 mph or higher to keep the voltage high?

If I would need to take a guess without a technical explanation. To keep gas mileage low in city driving conditions, even if it represents 0.09 M more per gallon, at least the alternators, work less and will not need to have to be replaced more frequently, at least with the RL's.

On another topic.
I tend to not be a fan of the big 3, simply because, listening to music with the engine off will not increase the voltage, or offer any benefit, having a good gauge wire from the bat to the amp and good grounds is more important to handle more current and reduce any voltage drop.

And I have set the gains, on amplifiers with the engine on and off, and I listening I can't honestly tell the difference in power output, perhaps some peaks and transients that can be measured but not heard.

No experience with SPL comps, although in sq comps, in certain classes, since there is like 6-7 diferent levels of sq competitions, each class depends on driver's locations, I've have seen systems in the upper range of classes with multiple batteries, 4 amplifiers and even 3 12" subs, do very well, but sq it's more about the tuning than the loudness, and any fraction of points earned, count to win,
There are other categories like best installation, best show car with a system, and RTA competition also. Again all this is extra information that does not relate to having the ELD bypassed or having to do it since, the engine is off in SQL comps, they judge on battery power only.

 

[Scott1234]

Hi, Has anyone found the solution for the 60 MPH (under) to 65 MPH (over) voltage problem yet?
I'm basically having the same problem... (Below 60 I'm at 11.5 to 12.5 and around 65 and over, I'm at 13.5 to 13.7 etc etc etc)
Has anyone replaced the ELD unit yet? I've heard of those replacing Alternators and Batteries/regulator but nothing on replacing the ELD unit yet...

 

[Cochise111]

Couple of Sunday morning thoughts on the concept of "needing" to by pass Honda's load detection circuit:

First is: The premise is erroneous. The post linked to Steve Meade Designs overlooks the simple fact that if <14VDC is "needed", "low alternator" function can be defeated by simply leaving interior blower motor on @ low speed. All voltage/current available in an unaltered DC power system is now available to the audio system by use of a switch and circuit control method that's already right there. No hacking into factory wiring is required. Problem solved.

Second is: The premise is that to achieve rated output, amplifiers require 14VDC. What happens when less than 14V is available? Less current at the output terminals = reduced acoustic output. Hence, the perceived "need" to by-pass ELD is focused on a premise that more is better. I've not bothered to look into the output deltas between audio amps limited to 12V vs having 14V available because I don't really care. For me, eeking out the drop of power is a dragon chase I don't care to participate in.

Generally speaking incremental increases in power output are meaningless to the sonic landscape projected by a given system. Without getting into the LONG history of human hearing sensitivity, suffice to say that each 3db increase in acoustic output of a system - no matter what kind or where it is installed - requires doubling the number of watts from the amp(s). Ponder that for a moment. To make even the smallest audible difference in a 500W sub amp, you'd need to step up to 1KW.

Can your ear hear a 3db increase? Therein lies a great never ending debate - the real answer is yes and no. It has been proven, over and over and over again through lengthy lab, listening and blind testing that the perceived benefits of the "3db delta" is subjective at best, and real world listening tests are inconclusive. The issue might be best compared this way: two identical cars, configured exactly the same. Both measured on a dyno. One measures 200HP at the drive wheels, the other 215HP. Can you feel the difference in your butt dyno? If those vehicles ran 25 back to back 1/8th mile drag races, would 215HP stomp the 200HP every time?

In the context of a DC powered audio system, a healthy supply is always a good thing, but volts and current are whats needed for sustained and impulse output in any audio system.

If someone is interested in getting the absolute best out of a system and has unlimited funds, the worlds shiniest hot rod sporting the most outrageous audio system can be built. Your mind can be blown by chrome and billet, wires and connectors, amps and speakers, time aligned this and that, but down here in the real world where drivers live and work, we want to enjoy our rides and get the best bang for the buck. This hair splitting stuff often leaves reason in the weeds. 2KW vs 1KW system. Cost, current demands on the supply system, space requirements, ETC, all for a 3db increase that may or may not be heard - but hey, bragging rights are worth the effort and expense, eh?

I'm one who scoffs @ the on going discussions around 14V mobile power supply systems requiring dedicated, secondary alternators and battery system. It's pure absurdity IMO.

Want the best DC system for your system? Audio nuts would do well to invest in deep cycle batteries connected to the the starting battery via an isolator. Most use cases wouldn't require beefing up the alternator either - although thats probably a good idea. By having a dedicated supply for the amps, impulse voltage and current is retained, the OEM charge system remains unaltered & starting battery life is maximized. While the RL is challenging for big audio in the cabin, the trunk is a prime spot for a mondo batt system. IMO: that's where power seekers should focus attention.

As far as "monster systems" go, quality (timbre, nuance, color, tone, flavor) vs. quantity (neighborhood disturbing SPL) are two very different things. IMO: the factory DC system is plenty good for powering a fine audio system. It would probably do OK for SPL freaks too - but the RL ain't real friendly to those guys unless they are willing to loose the back seat.

There's something about the car hobby that drives reason (at least my version of reason) out of the conversation. Saying it again: don't worry about iddy biddy incremental things that make little difference. Make informed decisions about every component in a system within your budget, keep the DC system healthy but don't alter circuits known to be reliable over millions of collective miles, be mindful of installation details, relax and enjoy the ride.

Back in the old days I fried three alternators in my 280ZX with my overpowered audio system before I installed a deep cycle battery and an isolator. Luckily I owned an auto repair shop and Napa warrantied the alternators. I neglected to tell them about my amps.