Lidl Ultimate Speed ULG3.8 B1 Battery Charger Design fault and Simple Modification

This is a great little unit but with one MASSIVE flaw in the design. If your car battery drains too low this charger wont recover it. Let's test it and see if we can apply a simple modification to make it work..

[@yongli2223]

The flashing icon of the car battery does NOT mean battery error, rather it means the charging mode is a Pulse charging mode! This pulse charging mode is used to repair or revitalise a severe discharged or fully flat battery and is rather useful.

[@razenby]

if only it worked!!

[@eduardonunomarques]

I borrowed one of these because of a flat battery. The lender couldn't find the instructions so I started looking for videos on how to operate it. I thought the blinking was an error because of this video. I kept insisting because it's not like I had all that many options, and eventually left it blinking. After a few minutes it went into normal charging mode. This was the only video on this version of the charger, and it is wrong. The glib response to someone pointing out the error does not look good.

[@tubularificationed]

yes, this is by design. If the "half full" LED is flashing, but neither of the upper-row LEDs is on (and can't be turned on via the mode button), that means: "congratulations, you have more than 7.5V, so I am going to charge it soon as a 12V battery. I just haven't decided yet, if this is really a flat 12V battery, and not a freshly overcharged 6V battery. So give me a few minutes to monitor the voltage. If it will be stable and long enough above 7.5, then I'll start charging assuming a flat 12V battery. After these few diagnosis minutes expired, it automatically starts loading (not requiring you to press the mode button). It enters the small motorcycle battery mode (0.8A max), to be on the safe side. From then on, you can upgrade the charging speed to car battery mode any time, with pressing the mode button. The "half full" LED keeps flashing while the charger is in the pulsing phase (which aims for reducing sulfate crystals on the lead surfaces). Once the voltage exceeds 10.5V, it moves on to regular charging (0.8V or 3.8V), and the "half full" LED is on continuously.

[@Maffey]

Can't believe your video was the only one that explained what the all four blinking lights meant. Thanks!

[@razenby]

Thanks for watching - good to know I got something right! Do me a favour and subscribe.

[@gerrym1582]

Where in the video is this?

[@Maffey]

​@@gerrym1582just checked the video, see 7:30 - 8:00

[@gerrym1582]

@@Maffeythank you so much, trying to charge my cars battery but all I’m getting is this 😢

[@Maffey]

@@gerrym1582 haha was in the same situation, browsed like dozens of articles and manuals before finding this video ♥️

[@pimlicobat]

Takes me back to my Regentone days, 1957!

[@razenby]

That wasn't my intention - the law of unintended consequences strikes again!

[@G7EXZ]

Thanks for your time explaining how the unit works & your mod to improve its worth. I've had one of these for some time that I bought in a second-hand shop but I was exasperated to find that it couldn't charge a "flat battery" I'll be sure to check it charges a battery with a voltage greater than 11v and then I'll set to on improving mine with your upgrade too. Many thanks ;)

[@razenby]

Glad you found it useful.

[@colin5064]

Amazing modification for real world usefulness,just wish l had your knowledge and experience

[@razenby]

Glad you liked it... Maybe get a soldering iron and a multimeter and start exploring,,,

[@bmp0149]

This is a nice review, taught me a thing or two about the circuitry. I have the later version with LCD display which had the desulphiting function as the Aldi version you reviewed. Mine has date of manufacture as 2014... and has just died. It lit up like a lattern briefly while it fried itself internally. To cut a long sort short it's the rectifier diodes that have gone, taking out the on board fuse and some of the circuit board copper track. Now mended but life expectancy is ??? Looking around, it seems like lots of them die just out of warrantee, 3 years, not so good for low usage electronics. Maybe the later LIdl 5 amp red one will be better.

[@razenby]

Design fault. There is a rectifier diode in the bootstrap supply goes short. After the video the locals found out about me and the channel and thought I was a repair man and I have fixed about 10 of them now. It is usually a 3 cent diode. There is another video that details the repair. Easy to check if you have a multi meter. But don't plug in when open unless you know what you are doing.

[@kitecattestecke2303]

Well the first versions where like this in the Video from the interface and features just the case is much square, i have it for several years and it charges anything fine just hold the mode button... What both of you experience is classic product life cycle and pressure from the discounter accountant who are stupid penny pinchers.. The early version is much better

[@anthonywheeldon1181]

Hello again..well following my comments from a couple odd days ago & while thinking about ordering the components mentioned in your video I decided to have another try at charging a flat battery with my earlier A1 model which at the first attempt displayed exactly the symptoms of your later model B1 AND did so again with my second attempt. The battery in question was a 55Ah 255DIN A approx 425 CCA sealed lead acid battery run flat accidentally by me not switching off the lights...battery terminal voltage 4.5 volts. So Sunday evening I connected the charger, switched it on and again could not get into the Mode 3 charging mode for this battery rating..no matter how I tried..the only Indicator lit was the charging diode flashing every couple seconds or so..and the battery terminal voltage fluctuating between 4.5/6volts.. ( pulse charging mode???)...this time I decided to leave it on as I had time on my hands being well past pension age and now on lockdown. Checked it again about a 1/2 hour later & still the same..left it again for about another 1/2 hour or so..low and behold this time the mode 2 indicator diode was lit, the flashing charging indicator was out but the green fully charged indicator was lit ..??....then I tried mode 3 which lit up but the green indicator remained on not switching to charging mode for the higher capacity battery...IMPOSSIBLE ....I thought..I switched off the charger..tried the lights which shone quite brightly but the twin tone horns would not sound the relay clicked limply..not enough power obviously..so switched on the charger again ..pressed the mode button and now able to scroll to mode 3..the red charging indicator lit up this time continuously and remained like this overnight and all the next day with me checking it periodically when at about 6.45 pm when the battery terminal voltage reached 14.18 volts and was still charging..left and went for a cuppa returning to check things @ 7.15 pm..the red charging indicator had gone out and replaced with the green fully charged indicator..AND now in trickle charge mode with the battery terminal voltage at 13.5/13.6 volts ... Lights now very bright, twin tone horns almost deafened me in the confines of the garage AND the car started on the third turn of the key. JOB DONE!!!! About 26 hours from start to finish seemingly a long time BUT the charger only charges @ 3.8/4amps maximum so if it would charge It I expected it to take at least 24 hours to fully charge this battery. NO I cannot tell when the battery had enough charge to crank the engine as my interest was to see if it would charge up a flat battery WHICH IT DID. So as the later B1 charger highlighted in this very interesting video presentation had exactly the same symptoms as my earlier model... given the time I would expect it to be able to charge a flat battery in similar circumstances to mine. Regards

[@razenby]

Interesting

[@chris_hayes]

Brilliant, gave me enough info to fix mine. :)

[@razenby]

Good Job!

[@bzcup]

Interesting mod that I have only discovered it now when my charger just died. I think the uP died as no leds turn on but relay does after 1 second and delivers 16V at the output without pressing the button. I guess I needed to upgrade to the display version anyways 😂

[@razenby]

Sounds like it is over for you poor charger...

[@NissanN12Dude]

Interesting mod, thank you for the excellent show and tell! Noticed that you have done a comparison of the newer 5 amp Ultimate Speed ULGD 5.0 A1 model and the ALDI AutoX. I'm wondering, do you have any plans to do a similar modification on the newer 5 amp Ultimate Speed ULGD 5.0 A1 model as the one you did here on this ULG3.8 B1? Would be interesting to know if such a mod can be done and how.

[@razenby]

I have come up with a very simple method to do this - I will release a video when I have a moment.

[@NissanN12Dude]

@@razenby Nice, looking forward to it, thanks!

[@user-sh2hg8es9r]

Won't you tell me what kind of chip you soldered the wires to? Marking CR201.What kind of chip is this?

[@razenby]

Sorry I don't have one the bench to check out the chip.

[@user-sh2hg8es9r]

Спасибо за ответ.@@razenby

[@TR5Q3]

A 12v battery is dead at 10.5v. It would be considered as being almost exhausted at 12.0v. Fully charged and left to settle it will read 12.7v or more. It not charging below 10.5v is a protection, and this works as it should.

[@razenby]

Um no. The semantics of what is flat and what is not is irrelevant. It is too clever and too versatile and a jack of all trades and master of none. When you wont start because you have left the lights on and you need to go to work then you need CHARGE!!

[@llaci80]

@@razenby i have same charger, i never seen before but the manual say 7,5 -10,5 V +-0,5 volt doing impulse charging while repair battery, can you test it??? or ..that is totally fake ? sorry for my english

[@blackestknights]

@@razenby I have had a battery this bad and it will not charge without some help, a set of jump leads to another battery will force it into charging mode. I just found this video because mine was flashing at 10.5 volts saw the post about pressing the button twice and went out to see a motorcycle symbol then just switched it to car mode. probably just 5 minutes to get it charging properly.

[@nixonsmateruby1]

Quicker to charge 2 battery, or, like I'm doing, taking it straight back to the shop, because on the front of the box it states that it will charge flat batteries, but booklet inside says it won't.

[@razenby]

I guess it depends on your definition of flat....

[@Radfordperson]

Hi there, interesting video. I believe that the charger shown is quite an old version. For several years Lidl has sold a later version that has a digital voltmeter display. A couple of hours ago I went over to a neighbour that had flattened his car battery. I removed the battery and measured it's voltage with a multimeter. It was 4 Volts! Using the later Lidl charger, the charger read 4V, pressing the button on the charger, the voltage did not change initially, but after a few min the voltage had risen to 10V. The charger must have detected the flat battery and given a series of pulse charges. Later the meter on the charger showed around 12V. whether or not the battery is usable I don't know as yet. I shall go back to him tomorrow to see what has happened.

[@razenby]

Interesting. The charger featured in the video was purchased from a UK LIDL during August 18. The new Aldi Xs MD18559 charger available now is almost a copy but does have a recovery mode.

[@Radfordperson]

I can only think that yours must have been old stock. This video is nearly 5 years old. kzbin.info/www/bejne/hICcfoqbq7dkr80

[@MeFixingEverything]

Thank you so much. I will do this on my one.

[@razenby]

You’re welcome 😊

[@lo0k775]

There is option to charge flat battery. Just press mode 2x quickly and it will flash second bottom light.Just wait till it come back to standby. Some time u have to do it couple times .When its done u can charge normaly.

[@razenby]

Only if the O/C terminal voltage is above 7.5V on a 12V battery. Otherwise you are stuck in 6V Mode..

[@fr.tedcrilly1406]

Hi, Thanks for your video. Could you please tell me if the sense voltage is injected in the same place, R57, for the ULG 3.8 A1 version? It’s very similar but doesn’t have it on the underside like your video, but has on the topside on a little vertical pcb off it. Thanks Conor

[@razenby]

Sorry I don't know. I gave all the LIDL batter chargers away, It should be fairly easy to find. It will be a resistor potential divider. One end going to the Battery + Output , the other to the 0V rail and the midpoint tracking back to the microprocessor or a comparator chip.

[@sL1pKn07SpinFlo]

Hi, in the min 29:40, why i can see joined all components in bot sides? i mean, the diode, resistors and capacitor (upper) is joined. ok, but in the down, you also joined all components? or is a visual effect? the red wire (5v) is connected only to the 1K resistor (right side), right? the protusion from the right resistor to the middle resistor can made a mistake greetings

[@sL1pKn07SpinFlo]

as note. i have the same unit (2015) and a possibe faulty(?) Bosh S4 60Ah with 10.50v. if power on the unit and press mode button, the charge led turn on. but all mode leds is off. (only i can swicth between this step and power off). when pass more or less 2min with this status, the charge led start blink (and the relay sound click one time) alternatively with the full battery led (green). in the output oscile between 13v and 15v. then the mode bike led is on and i can change between modes (car and freeze modes, the 6v is unavailable) and power off.. but when pass 20/30min the unit power off automagically (power led is on).and nothig suceded. i can repeat the process lot of times. but the battery not charge or start to charge. the voltage remains the same whit this mod i can recovery this battery? greetings

[@razenby]

If the battery has been at 10.5 volts for more than a few hours a long time then it is ruined and cannot be recovered. Ifthe battery is presenting an overcurrent or is not correct then the charger will do strange things.

[@anthonywheeldon1181]

Really interesting video...my Lidl charger is the earlier ULG 3.8 A1 version (booklet dated 2012) and I've become aware of this problem..despite the booklet suggesting otherwise. The display is exactly the same layout as yours with the only noticeable difference the shape of the exterior case moulding. Do you know if '"my circuit board" is the same as the one demonstrated and if the components highlighted in your excellent video would be any good for modifying my charger ?? I'm not an electronics specialist so would be useless at working out my own circuitry. Finally I did manage to remove the base to take a peek inside after managing to loosen the special head security screws, but the circuit board seemed to be reluctant to lift out of the grey upper casing and wondered if in your project it was held into the upper casing with some sort of adhesive..Any information would be welcomed so Thanks again for sharing your solution with us. Regards

[@razenby]

No problem.

[@drumloughhall1635]

Hi, I have a Ultimate Speed ULG3.8 A1 with the same problem. Have you ever moded this model or have you any ideas as to how to go about solving this one? Outside of the box looks similar except the mode button is round, and inside the circuit is completely different.

[@razenby]

No, not seen that one but there is sure to be almost the same circuit inside. If there are no signs of burning then check the bootstrap rectifier diode and any Zener diode associated with it,

[@markellis4229]

I would love this modification of mine 👍

[@razenby]

Good luck.

[@Chris-zt3zx]

Thank you for this upgrade. I have made this upgrade but i must keep the push button "on" to have the red light of the car battery "on". If i release it the red light off the car battery turns "off" with the noise of the relay. My car battery is a 61 AH and his voltage is 10.2 v. I hace check twice the upgrade and all teh components. What do you think about that ? May i change the push button with a switch to keep the charger "on".

[@razenby]

Not sure, If left connected the standard charger should charge the battery but slowly. If not the battery may be faulty. 10.2V suggest that it may have 1 shorted cell.

[@naskok211]

Hello. I have same charger and when I connect to the car battery all lamps on top start to blink. Do you know what does means?

[@razenby]

If teh car battery is below 3 volts it will blink and cannot start charge. This charger will not attempt to charge a really flat battery. See modification video for this model for a full explanation.

[@zx8401ztv]

Very sneaky, just the job :-D

[@razenby]

Thanks

[@supernova1976]

Thank you for sharing this , as you mentioned this charger can be left connected to the battery for a very long time. i was wandering how long is very long, reason for asking, i need it for my fathers car , he doesnt use the car for months and every time the battery is so flat it is usually dead after few months. can i leave it connected to this charger for 3 months at a time ? an i am assuming i have to remove any load i.e. the battery leads in the car so it is a direct connection between battery and charger.

[@razenby]

Thanks. This charger is good for long-term charge support for a car battery. The only issue is that if there is a power outage the charger does not automatically resume what it was doing - It remains off when the power returns. This means that it will be necessary to periodically check that it is turned on.

[@supernova1976]

@@razenby thanks, that's a very good point. Thankfully there is never a power outage in London .

[@heikg]

So first recommendation: don't buy lidl shut Second recommendation: do the 1min fix first and then do the 30min video explaining how the fix works The fix is at 16:40 for the people that don't wanna pass an engineering class afterwards and just want a car that starts

[@razenby]

And your comment is deleted!! HAHAHAHAHA

[@paulmuff9883]

Brilliant 😀😀👍

[@razenby]

Thank you! Cheers!

[@MrTurboSAAB1]

Hello.Is this design fault present at latest 2019-20 model /red housing/ ? Is this charger capable as power supply /telescope mount/? Greetings from Slovakia.

[@razenby]

Hello, I am not sure. It is an OK charger if the battery voltage is above 7.5 volts. An important factor to consider that if a 12V lead acid battery terminal voltage drops to 7V for more than a few minutes then it is ruined anyway ad will never have full capacity again. It is not useful if you have left your lights on and you want to get the car sufficiently charged to go to work. If you don't need a 6 volt charger then as an all-round cheap charger the 8A one reviewed on this channel is a similar price and is useful in more scenarios.

[@Tab7.6.Tab7.6]

Hi, do you still have this charger? If yes , do you know how to raise the final voltage to 15.1V for example? In the older version (A1) there is a potentiometer for this, I don't see any here. Is there also an HT46R52A controller in this version?

[@razenby]

Just adjust the resistor divider ratio on the chain that is connected to the battery terminal wires. You will have to calculate the correct value of quite high value resistor and connect it in parallel with the lower resistor in the PD.

[@Tab7.6.Tab7.6]

@@razenby Thank you very much 👍

[@OcantinhodoDragonBall]

After fully charging the battery how long do you think the battery will last?????

[@razenby]

Depends on the condition of the battery,

[@josefmynona4228]

Hello, great video. I have bought ULGD 3.8 B1 charger, which is version with display. I soon realized that it did not charge properly, battery had only 12,2 - 12,3 V after completed charging cycle. So I tried again and I found out that the voltage indicated on charger was 0,5V higher then real voltage was so charger "thought" that battery was fully charged and stopped charging but it was not. I claimed charger, got new one and this had the same fault as previous one, so it seems there is some either design issue or some faulty component(s). I quicky watched your video and you somehow tepmorarily fooled charger so it thought battery voltage was actually higher. I need in principle same thing - I need to alter some components to make charger think the battery voltage is lower(= accurate) and thus charge more/longer. Would you give me some advice as I expect more people who have bought this charger have the same problem. Thank you

[@razenby]

It is probably a tolerance problem in the divider resistors or the voltage reference on the microprocessor. The micro uses an internal reference to compare the A to D measurements. The trouble is that these cheap micros can be way out. I suppose you have checked that your voltmeter (multi) is accurate? If you want to correct the reading than put the charge into low current mode and wire a high impedance potentiometer across the lower potential divider in the chain. Since you are looking for an adjustment of 10% try a potentiometer vale of 20 X the lower resistor value. Start with pot set to max and then adjust.

[@thatwasthedaythatwas]

Hi. I am very interested in using this unit for two leisure batteries. I’m hoping to buy two 100ah batteries. Would this unit charge the two? Many thanks

[@razenby]

Yes in theory - fine if you want to keep them healthy in storage (No load). As soon as you use them (discharge) and the voltage drops below about 11 volts they will cut out. So as a support charger/ monitor (maintenance) to keep battery topped up = fine BUT for leisure use = not fine. You might want to consider using two chargers - one one for each battery..Connecting the batteries in parallel is not a good idea.

[@nixonsmateruby1]

I have just bought one today but on reading instructions it won't charge unless it's charged? Haha.

[@razenby]

It wont charge a 12V battery unless the terminal voltage is 7.5 volts or above. It is to do with it being a universal 6 and 12V charger. It cant tell if a battery is a fully charged 6V or a very flat 12V.

[@azala581971]

Is this mods working also in 6v mode ?

[@razenby]

Yes It is fine. I didn't bother testing it as very few people need 6V mode.

[@azala581971]

Update Ive made this mods and working great in 12 v mode. When conect to 6 v small gel accu with boost pressed detect as bike aku in 12 v mods and i can choose bike car or trickle charge. Is there solution to down to 6 v mode after boost choice ?

[@razenby]

@@azala581971 Yes, just wait till the battery voltage comes up and then disconnect everything and reconnect. If the 6V battery has got some charge then it will run normally without boost.

[@azala581971]

@@razenby May I ask I ve noticed that current at 12 .7 charging is 0.8 not 3.8 . I get my charger fom electro rubish so maybe id defect inside. Could you please advise what check inside first ?

[@razenby]

@@azala581971 Hi Andrew, I cant be sure. Does it ever charge at 3.8? (Has to be on car setting).

[@AJ-ql9xx]

This charger can charge battery 200A?

[@razenby]

You mean 200AH ? Sure but it will take about 3 to 4 days.

[@AJ-ql9xx]

@@razenby aha Thank you

[@davidcromie2689]

I have one of them chargers with the same problem if I sent it to you could you help me to fix it for me please ill pay you

[@razenby]

Hi David, sorry , I am inundated with paid repair and design work at the moment.

[@davidcromie2689]

Thanks for you reply I have a man watching your video now and he is going to fix mine for me

[@hiranjayasekara3522]

My charger was burned due to spike..need your help to fix this..can you share Skype or WhatsApp?

[@razenby]

Sorry I have no time to help. Working on a design contract now...

[@pawol6201]

on the box I see "pulse charge to recharge flat batteries". So, your modification is useless :(

[@razenby]

A little understanding is a bad thing. Did you even listen to the detail or are you guilty of Low-resolution thinking. In any case you are wrong.