I have a DEFA Smartcharge 4A for use in my garage, mainly for being able to tinker with OBDEleven and other menu settings with the engine off, without the fear of draining the battery, as well as for unexpected incidents.

However, when I tried to do just that yesterday evening, I noticed from OBDEleven that the battery charge status was dropping despite having the charger connected, by a pace of 1% every 1-2min. Electrics are not my specialty but could it be that the car has such a high electrical consumption when playing with the menus or working the CANBus that I need a stronger charger to at least maintain the charge status while I am doing adaptations?

The details of it can be found here for whoever is interested:

https://www.defa.com/product/smartcharge-4a/

 

Have you enabled the DRL menu in the infotainment?

 

Turning the DRL’s off can help a lot. 

I posted recently in this thread, asking after recommendations for a charger, the one I saw was on offer from Euro Car Parts, but at 7Ah it was deemed far from powerful enough.

 

If yours is a 4Ah then presumably the car is drawing more than your charger is able to put back in?

 

 

Just now, Gizmo said:

Have you enabled the DRL menu in the infotainment?

 

Turning the DRL’s off can help a lot. 

No I haven't. I could try and see if situation improves but then you're saying that it's possible for a 4A charger not to be that strong to at least maintain the charge?

And do we have any idea how much more powerful it would need to be to do that? There are 6, 8 and 10A variants.

3 minutes ago, newbie69 said:

see if situation improves

It definitely will. Try it.

Trouble with some "smart" chargers is they operate in stages in a one way fashion, once they go to the final stage, maintenance mode, they often turn off, will wait for a certain time to allow the battery to rest, could be an hour or more and will not turn back on until the battery voltage drops to a defined level.

 

If all the vehicle systems are active, as they will be when playing with OBD11, the consumption is indeed several amps.

1 minute ago, silver1011 said:

I posted recently in this thread, asking after recommendations for a charger, the one I saw was on offer from Euro Car Parts, but at 7Ah it was deemed far from powerful enough.

 

If yours is a 4Ah then presumably the car is drawing more than your charger is able to put back in?

 

When left charging overnight it has charged other batteries fine, so I guess it works in general, but never tried it with the ignition on and certainly not on a Superb where I suppose consumption might be higher.

Was just wondering if anyone had a value in mind out of experience of how strong a charger would need to be, to be able to do what I want: Try adaptations without at least losing charge. Or would that be not possible at all with most chargers? 

I'm scared to even imagine how fast the charge would drop if I hadn't connected the charger at all and stayed for 10min!

3 minutes ago, xman said:

Trouble with some "smart" chargers is they operate in stages in a one way fashion, once they go to the final stage, maintenance mode, they often turn off, will wait for a certain time to allow the battery to rest, could be an hour or more and will not turn back on until the battery voltage drops to a defined level.

 

If all the vehicle systems are active, as they will be when playing with OBD11, the consumption is indeed several amps.

That makes sense.

Also, another question on the topic, there is this particular mention in the user manual:

14.7V button
Some batteries require a higher charging voltage than other batteries.

If the 14.7V button is activated the initial charging voltage will be 0.3V
higher than the standard level.
Before activating this button, the 14.7V charge voltage requirement should be confirmed.

If a battery requires this higher charge voltage, it will be described on the battery

 

Any idea if the Superb's battery is such a case where I would need to activate the 14.7V mode? Didn't see that number when just looking at the battery.
 

The OBD11 "charge" readout might just be based on Battery volts. Battery volts initially drops quickly when ignition is turned on but does not indicate charge level when you are drawing a current.

 

Don't take it as being very accurate.

1 minute ago, newbie69 said:

That makes sense.

Also, another question on the topic, there is this particular mention in the user manual:

14.7V button
Some batteries require a higher charging voltage than other batteries.

If the 14.7V button is activated the initial charging voltage will be 0.3V
higher than the standard level.
Before activating this button, the 14.7V charge voltage requirement should be confirmed.

If a battery requires this higher charge voltage, it will be described on the battery

 

Any idea if the Superb's battery is such a case where I would need to activate the 14.7V mode? Didn't see that number when just looking at the battery.
 

 

14.7v only to be used on vehicles fitted with AGM (Absorbent Glass Mat) batteries. Look at your battery. In big letters it will either have AGM or EFB (or  just a big E). EFB stands for enhanced flooded battery and should only use the lower voltage setting.

You didn't have the climate still on did you? Sometimes if the blower is on low you might not notice it but will still be using power.

 

Even with no charger on my car I have sat in it playing with VCDS for between 1 and 2 hours no problem so I think you are either being fooled by the charge readout or you have too many lights/equipment on.

 

3 minutes ago, xman said:

 

14.7v only to be used on vehicles fitted with AGM (Absorbent Glass Mat) batteries. Look at your battery. In big letters it will either have AGM or EFB (or  just a big E). EFB stands for enhanced flooded battery and should only use the lower voltage setting.

 

Or normal batteries in cold weather (I only mention because this mode on my Ctek is a snowflake icon but it does mention in the manual that it is to be used if charging AGM batteries also)

 

Edited 3 March, 20197 yr by SuperbTWM

Cheers for the replies. I think I might be worrying too much with the "charge" indication but in any case I'll try to turn off as many features as I can see that are known to be consuming a lot.

1-2hr playing with VCDS without external power supply sounds too scary but maybe I'm wrong on this!

Regardless, I think my plan of sitting in the car and enjoying my music while trying settings is gone... 

Just now, newbie69 said:

Cheers for the replies. I think I might be worrying too much with the "charge" indication but in any case I'll try to turn off as many features as I can see that are known to be consuming a lot.

1-2hr playing with VCDS without external power supply sounds too scary but maybe I'm wrong on this!

Regardless, I think my plan of sitting in the car and enjoying my music while trying settings is gone... 

Columbus will still be turned on but muted!

 

I think it will warn you if battery is low (not 100% sure)

 

Keep your charger connected and turned on while messing about, it will definitely help.

Just looked at the charger manual. 2 important bits

 

Long-term charging After the battery is fully charged,  the charger will go in  to  Sleep  Mode. This is indicated by all battery LEDs slowly pulsating.  This mode has a very low power consumption. After a week in Sleep Mode,  the charger will wake up and begin a new charging cycle. The charger will also wake up and start a charging cycle if battery voltage drops below 12.6V.

 

Confirms what I thought, but has this useful feature , Power supply mode, just what the doctor ordered, so use it!!

 

Power Supply mode Keep pressing the button until the LED shines one by one in a regular buttom to the top cycle,  the charger will start power supply mode.  In this mode, the charger supply 13.6V. If the output short circuit or connect with incorrect polarity in this mode,  the charger will go into error mode.   You should press the power button to turn off the charger,  then restart the charger (go to charger or power supply mode).

Edited 3 March, 20197 yr by xman

4 minutes ago, xman said:

Just looked at the charger manual. 2 important bits

 

Long-term charging After the battery is fully charged,  the charger will go in  to  Sleep  Mode. This is indicated by all battery LEDs slowly pulsating.  This mode has a very low power consumption. After a week in Sleep Mode,  the charger will wake up and begin a new charging cycle. The charger will also wake up and start a charging cycle if battery voltage drops below 12.6V.

 

Confirms what I thought, but has this useful feature , Power supply mode, Use it!!

 

Power Supply mode Keep pressing the button until the LED shines one by one in a regular buttom to the top cycle,  the charger will start power supply mode.  In this mode, the charger supply 13.6V. If the output short circuit or connect with incorrect polarity in this mode,  the charger will go into error mode.   You should press the power button to turn off the charger,  then restart the charger (go to charger or power supply mode).

Does that mean in Power Supply mode it will allow charge to drop a little before charging up again? Because I think I might have used that setting assuming it won't allow a drop, not sure but I'll go out and check it in a while.

Edited 3 March, 20197 yr by newbie69

Other thing worth doing  - if you have a multimeter that measures current - is to put that in series with one of the charger leads and see what the charger is actually doing, current-wise, when ignition is on.

Power supply mode sounds exactly what you need though. Try that and see if it stops the discharging (after switching off any lights and fans you can).

Power supply mode will constantly supply up to 4A (current limited) at max of 13.6 volts. Trying to maintain 13.6v. Just whats needed. Definitely use this. It will allow you to play for an hour or three.

Ok guys, I'll go out to do some testing now and report back.

Hey, forgot to add. IMPORTANT. Make sure you connect the charger correctly. As per user manual. Positive to positive terminal of the battery and negative to the Chassis Tab and NOT the negative battery terminal. If you don't do this, the battery management will get all confused and you will have all sorts of problems. This is because there is a current sensor in the battery negative terminal connector that tracks the charge being taken in or out of the battery.

1 hour ago, xman said:

Hey, forgot to add. IMPORTANT. Make sure you connect the charger correctly. As per user manual. Positive to positive terminal of the battery and negative to the Chassis Tab and NOT the negative battery terminal. If you don't do this, the battery management will get all confused and you will have all sorts of problems. This is because there is a current sensor in the battery negative terminal connector that tracks the charge being taken in or out of the battery.

Yep, I am aware of using the chassis instead of the negative terminal but I didn't know why exactly 

Just been outside and got a bit of data courtesy of my newly gifted mk4 Golf 1.9 ALH

 

Bearing in mind the car has very little in the way of gadgets (although a Y Reg car with an auto dimming rear view mirror and isofix brackets took me by surprise)

 

Ignition on, everything else off, no glow plugs - 2.9 amps 

Ignition on, interior lights on with door open - 5.1 amps

Ignition on, interior lights on with door open and headlights - 16.7 amps

Ignition on, interior lights on with door open, headlights and glowplugs 70+ amps (ramped down as glow plugs heated up)

 

So basically, turn everything off that you can possibly turn off and your 4 amp charger may just be able to keep up!

 

12 hours ago, Gizmo said:

Turning the DRL’s off can help a lot. 

what a suggestion, in Scandinavia and Baltic States DRL’s must be ON all year round

 

in winter season, when 0 kms outside the city, my car's Start-Stop doesn't work at all.
when engine is on i see 14.2-14.6v, but when turning off it fastly (3 minutes) stepping from 12.5v to 11.5v
after 5 days long service visit i weren't able activate Webasto cause low battery

13 minutes ago, MartiniB said:

what a suggestion, in Scandinavia and Baltic States DRL’s must be ON all year round 

 

Quite rightly IMO

 

If you wish to quote me then please quote everything that is relevant:

 

12 hours ago, Gizmo said:

Have you enabled the DRL menu in the infotainment?

 

Turning the DRL’s off can help a lot. 

 

Nobody is suggesting to turn off the DRL’s permanently, just whilst coding. 

^^^

guilty, i weren't read enough careful,

there were about "DEFA Smartcharge 4A",

but i meant car's charger which "not up to the job" while city mode only

 

I am anal about battery longevity. So I turned off the coming home lights, always turn off stop/start as well since I hate it. 

 

Don't forget if coolant is warm, the fan does work for a while after engine is turned off too.