48volt system i got 4 deep cycle 12volt batterys. Would like 2 know how 2 hook up.

Batteries can be charged parallel using the correct voltage but it's always better to charge them independently. This allows you to better evaluate the battery condition as well as making it easier to identify problem cells.

My suggestion is to never use the 100 amp start except when you have someone to crank the engine while you operate the charger. You really don't want to pump 100 amps into the battery unsupervised, it could explode if frozen and may even have other issues.

The 30 amp boost is a quick charge. Your best setting is the 6 amp which will build back the voltage gradually. The 2 amp is the slowest charge, some folks use this for deep cycle charging marine batteries and just when you are in no hurry to use the battery.

burnt circuit no internal fuse

I have an old 12volt motorcycle battery I keep charged and hook it up to the system before disconnecting the main battery. This prevents the possibility of the on-board computer / radio etc. losing memory

find a reputable battery shop ( not repco , supa cheap type shops )and discuss your requirements with them
go for calcium batteries or the like for long life as battery construction has changed a lot in the last few years
remember the bigger capacity battery , the longer it will run items so don't settle for a small battery when a larger ( if it will fit ) battery will be a better buy
warranty is 12 months standard up to 3 years but the price goes up for the warranty period

why does the blue box say 2005 swift and 03 polo?, confusing , so I will answer in the generic. (any modern car)

any engine dies for vast reasons, I have a list of 50 .
but breaks down to 4. (in pure physics) Otto cycle engines, GAS.

1: lost DC 12volt power to the EFI system( electronic fuel injection)
2: lost compression on more or all cylinders, 150psi min. is a goal.
3: lost spark, weak spark or mal-timed spark.
4: bad fueling, (too little , or too rich fuel injection)

The ECU works hard to sustain running, via idle speed control valve
and spark timing tricks.
when the above 4 go bad, the ISC function fails and the engine
stalls.
so does, skipping 60,000 mile tuneups. that cause any of the 4.

The same as a regular battery.

If your battery runs down when the car is off and not running, then you probably have a 12volt drain
killiongthe battery. If your problem occurs even when the car is being driven and used, then your alternator may be the culprit, it may not be charging enough. Attach a voltmeter across the + and - battery terminals. Start the car and let it idle without any accessories on. If you get a reading somewhere between 13.75 - 14.75 volts, your alternator is ok.
To check for a 12volt drain, disconnect the negative battery terminal and slowly scrape it on
the negative battery post 3-4 times. If you see any light to medium sparking as you do that, you probably have a 12volt drain killing the battery. BTW, don't be afraid of being shocked, no chance of that. This is extremely light voltage we're taking about here. Any 12volt drain is best left to a professional to trace down. Oh yes, a defective new battery is possiblity, but highly unlikely.

Hi, the deep cycle battery is for the home part and should charge through the external connector port. The regular battery is for the engine. Is the regular battery charged up too?

On Aftermarket Radio :

Yellow = Constant 12Volt
Red = Accessory 12 Bolt ( Key ON or on Accessory )
Black = Ground
Blue = Remote Wire for Amplifier
Orange = Dimmer Light

So you need to Route the Blue Wire to your Amplifier, if you connect the remote wire from the amplifier to your yellow one.. it should work but your sound system will Stay On all the time and eat up the juice of your battery.. !

Sams club $77 each