TIP: Charging battery or jumpstarting

[ychachad]

The cover on the battery clearly states "Disconnect negative terminal before charging battery or jumpstarting to avoid damage to car's electronic components". Simply put, disconnect the battery when charging, and also disconnect the battery when jumping. I confirmed this with my MB tech, who has experience on MBs for past 35 years. Crossing terminals can prove fatal. It is a pain, but it MUST be done.

[shmelvin]

I don't believe you could jump start the car without the cables connected, as soon as you disconnected the jumper cables or charger it would die as the circuit would be broken. I would agree that if you wanted to try and fast charge the car with a high amp/Voltage charger it would be smart to disconnect the battery. On the other hand given the inherent voltage leakage problems, keeping a trickle (maintenance) charger on the battery is no problem. I plug her in and leave it on at all times when it's in the garage, The dealer has never told me it's a detramental and always hooks it back up after servicing.

[7.3AMG]

When you "jump start" a car it is assumed the battery is either dead or really weak. Therefore when you jump start a car with a "weak" battery it doesn't contribute to the damage as much. This also applies to charging the car battery. It is assumed the battery is dead or weak therefore hooking up a charger should not contribute alot of damage as compared to hooking up a charger with a healthy battery... Still I believe disconnecting the battery before charging to be on the safe side.

The idea here is that even if you have 3 "12 volt" batteries connected together with all the positive and negative terminals together the end product is STILL 12 volts!!! The only difference is that it has more AMPS to turn the engine over and more stamina.

But if you take three batteries and connect them together using cross connection (pos. to neg, neg to pos.) then it would produce 36 VOLTS. Now that will burn your RADIO ECU etc!!