Trickle charge on Mercedes G63 AMG

[edyvw]

Not sure what year your M5 was. If you had an E39, chances are it was ok.
I'm talking about most BMWs after 2002, or whenever they started using the IBS sensor on the battery terminal. Then everyone started using similar stuff.
The story goes the car is better off when you charge through the IBS, so it can control things. Charging at the battery's poles bypasses it. Which won't damage the battery, but might damage car electronics.

You won't automatically damage the car if you charge directly at the poles, but there's a real risk. So if you have to do that - disconnect the car's cables first.

Which, in itself, is a whole different adventure, as a BMW has to go to sleep gracefully before you disconnect, which is a whole thing.

I put "German" together, as they all use such a system nowadays, one way or the other.

Yep, FRM might get fried. Lower chances of something else, but FRM is most vulnerable.

 

[edyvw]

No Euro car can survive being parked. I remember talking to friends of my in-laws about this, and they said how the transmission in their 7 series failed, and they only drove a car to church on Sunday. I said: "well yes, it failed bcs. You only drove the car to a church on Sunday."
They want to be driven, HARD! That's when they work the best. They are designed by people who drive every day on autobahn for autobahn. They ain't designed for a garage.
They can survive a long time without being hooked up to anything, as generally Euro cars come with really good batteries and huge ones. My BMW currently runs a 95ah battery, and there is an option to go to 105ah. I changed the original battery last year, the one from 2011, just because.

 

[goblin]

I agree that I might be confusing trickle charging with jump starting, and that the voltages involved are different. Still, I use the posts for charging.
I also agree about giving a jump start. I wonder if there's actually any voltage coming at the posts ?

 

[edyvw]

I agree that I might be confusing trickle charging with jump starting, and that the voltages involved are different. Still, I use the posts for charging.
I also agree about giving a jump start. I wonder if there's actually any voltage coming at the posts ?

They do. I think the manual says to hook the car that needs to be jumped to those posts. Those posts are basically "battery posts." Based on the cable that connects the post to the battery, I would say 2-4 gauge size.

 

[oilboy123]

The connection under the hood is the jump start terminal . You can put your charger there and there is a ground terminal near it.

I will go out and check it out again. Thanks

 

[OVERKILL]

You had E39. After 2004 and all BUS designs, absolutely on ports; otherwise, your FRM might get fried. Actually, no E60,90 etc. should be used to jump start anyone. When someone asks me to jump start them, I will go get Tiguan or a Toyota.

I'm not talking about a jump start though, just a low output maintenance battery charger.

 

[goblin]

I'm not talking about a jump start though, just a low output maintenance battery charger.

It should indeed not be an issue at all, unless your charger goes crazy.
The OP states that there's no voltage between the two though, I'm not familiar with MBs, but could it be that there's a diode that would limit or cut current from the battery to these poles ? Just curious.

 

[edyvw]

I'm not talking about a jump start though, just a low output maintenance battery charger.

Same. I think bcs. IBS. Also, it is really hard to connect in BMW positive directly to battery bcs. distributor.
I always use ports in front if I am doing something that requires doors being open or if purging air from coolant system.

 

[oilboy123]

It should indeed not be an issue at all, unless your charger goes crazy.
The OP states that there's no voltage between the two though, I'm not familiar with MBs, but could it be that there's a diode that would limit or cut current from the battery to these poles ? Just curious.

I must not have tried to get a voltage reading very well. I was trying to find a ground on the engine that is shoehorned into the engine compartment last time. Now I know to look out for the negative post that is brass colored I got a good reading. Only bad thing is I was hoping to charge with the hood closed? But that was asking too much.....ha

I just wish I knew how to drive it in 4 low. But my attempt failed the last time I tried...... It was not ideal putting it in my backyard, in high gear.

 

[GON]

I must not have tried to get a voltage reading very well. I was trying to find a ground on the engine that is shoehorned into the engine compartment last time. Now I know to look out for the negative post that is brass colored I got a good reading. Only bad thing is I was hoping to charge with the hood closed? But that was asking too much.....ha

I just wish I knew how to drive it in 4 low. But my attempt failed the last time I tried...... It was not ideal putting it in my backyard, in high gear.

My S550 has a nico charger on it while in storage. I am sure you can get the hood closed with the battery tender installed and operational.

 

[oilboy123]

My S550 has a nico charger on it while in storage. I am sure you can get the hood closed with the battery tender installed and operational.

The red alligator clip will be hitting the hood insulation/insulation. This engine is very tightly packaged. I'm going to find a way to get it where I can close the hood while on the charger.

 

[y_p_w]

Yeah - there's a jump starting post where a red cover slides to reveal it, and you should be able to find a metal point elsewhere to connect ground. There should also be no worries about sparking at the battery.

There might be an exposed brass post that's specifically for jump starting.

 

[f355spider]

No Euro car can survive being parked. I remember talking to friends of my in-laws about this, and they said how the transmission in their 7 series failed, and they only drove a car to church on Sunday. I said: "well yes, it failed bcs. You only drove the car to a church on Sunday."
They want to be driven, HARD! That's when they work the best. They are designed by people who drive every day on autobahn for autobahn. They ain't designed for a garage.
They can survive a long time without being hooked up to anything, as generally Euro cars come with really good batteries and huge ones. My BMW currently runs a 95ah battery, and there is an option to go to 105ah. I changed the original battery last year, the one from 2011, just because.

This! I have an H9 (105AH) in the trunk of my BMW M550ix, and an H5 (60AH) in the engine compartment. I was curious how much they go down without driving during the winter and tested them out to three weeks. It was clear the H9 was going to be iffy to start the car by 6 or 7 weeks as there is simply too much parasitic loss. Surprisingly the H5 showed no loss in three weeks. At the time, both batteries exceeded their CCA ratings. They are seven years old (original to the car) and the H9 still exceeds its rating, but the H5 is now slightly below. I do keep both batteries on a Battery Minder, with leads to the H5 and the jump terminals in the engine compartment to the H9.

I'm told the H9 is the starter battery, and the little H5 is used to run all the electronics when the car is stopped (engine off) when using the start/stop mode. Anyone know if that is true?

 

[edyvw]

This! I have an H9 (105AH) in the trunk of my BMW M550ix, and an H5 (60AH) in the engine compartment. I was curious how much they go down without driving during the winter and tested them out to three weeks. It was clear the H9 was going to be iffy to start the car by 6 or 7 weeks as there is simply too much parasitic loss. Surprisingly the H5 showed no loss in three weeks. At the time, both batteries exceeded their CCA ratings. They are seven years old (original to the car) and the H9 still exceeds its rating, but the H5 is now slightly below. I do keep both batteries on a Battery Minder, with leads to the H5 and the jump terminals in the engine compartment to the H9.

I'm told the H9 is the starter battery, and the little H5 is used to run all the electronics when the car is stopped (engine off) when using the start/stop mode. Anyone know if that is true?

Not sure about that setup, what runs what.
I got an E90 in 2019, and after a few months, I installed a DIY audio system with two amplifiers, and still, the OE battery did not budge.

When I decided to change, mostly bcs. I started to have issues with amp that was pushing two DIY subwoofers I fit into original enclosures under seats. The battery was still OK, but I had some issues with audio. Thought it was, well, 13yrs old battery. Turns out, it was a Pioneer amp. Battery was fine

 

[Vil_Riker]

It probably has another battery or two in it. Just use the terminals under the hood.