Battery Change and memory retention
#1
MBWorld Fanatic!
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Battery Change and memory retention
Has anyone used an ODB plug-in memory retention device when changing the main and gell-cell battery?
Just wondering if the ODB port is a good/better way to keep power going to the computer devices.
I am guessing that will all the circuits that cut off the regular power outlets, those are not a reliable way.
Just wondering if the ODB port is a good/better way to keep power going to the computer devices.
I am guessing that will all the circuits that cut off the regular power outlets, those are not a reliable way.
#2
Member
When I replaced my batteries, I attached a battery keeper to the jump starting terminals on the passenger side of the engine compartment... No drama. If you do this, do be careful with the positive battery lead when you are replacing the battery, as it will be "hot" and it can short to the body or any other ground, defeating the purpose of trying to keep the system powered whilst you are changing the batteries.
#3
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When I replaced my batteries, I attached a battery keeper to the jump starting terminals on the passenger side of the engine compartment... No drama. If you do this, do be careful with the positive battery lead when you are replacing the battery, as it will be "hot" and it can short to the body or any other ground, defeating the purpose of trying to keep the system powered whilst you are changing the batteries.
However I was going to use a small gellcell with a limiting resistor, because I don't like using a charger as a supply without a battery to smooth the voltage.
Some smart changers and tenders will even shut off if they don't detect a battery.
I just saw the ODB memory keeper and thought it was a unique solution.
#4
Member
Understand. If you are worried about instantaneous over-voltage by hooking a 12V power supply to your truck, then you could also attach any random 12V battery to the charging terminals. I just don't see a reason to spend money on a new gizmo for this procedure - you are a sophisticated wrencher and I know you have a bunch of reliable 12V DC sources you can choose from...
#5
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Understand. If you are worried about instantaneous over-voltage by hooking a 12V power supply to your truck, then you could also attach any random 12V battery to the charging terminals. I just don't see a reason to spend money on a new gizmo for this procedure - you are a sophisticated wrencher and I know you have a bunch of reliable 12V DC sources you can choose from...
Started having slow cranks if I let it sit a week, and since the car sits often for two+ weeks, and almost didn't start the last time it went two weeks without the tender, I figure it is time for a new battery.
The current battery has just over 6 years and 70k miles on it.
I am fairly sure they did not replace the gellcell when they did that battery, so I am going to do both.
#6
Member
I replaced mine after 5 years. I had a harder time wrestling with the auxiliary battery than the main - it is in contained in annoying thin metal enclosure with sharp edges.
For the main battery, I ended up going with the Bosch Platinum Group 49/H8/L5 AGM. I liked that it has a 4 year warranty. Got it at Pep Boys on sale - price out the door was $190.
I bought a relatively cheap auxiliary battery on-line from Interstate batteries. 12V 1.3AH AGM - Part #SLA105. Total $22 including shipping. Any AGM in that same physical size group should do.
To finish out the discusssion on the ODBII memory retainer - in my mind the electrical system of the truck is just wires that eventually all connect together. So you've got some sort of power source - either a 12V battery or a 12V power supply, that's getting connected to some very small gauge wires in your ODBII port, and those wires are eventually connecting to your main 12V power bus. How is that any better than just connecting a 12V Battery or Power Supply directly to the main power bus - I would argue it's worse because if you cause a short I would rather over-current is not traveling through very small gauge wiring in my ODBII port. I get why someone would build that product - in newer vehicles the cigarette lighters may be switched so the easiest way to get power to the system from inside the truck is through the ODBII port - I just think it's unneccessary and less than optimal for someone that knows what goes where under the hood.
For the main battery, I ended up going with the Bosch Platinum Group 49/H8/L5 AGM. I liked that it has a 4 year warranty. Got it at Pep Boys on sale - price out the door was $190.
I bought a relatively cheap auxiliary battery on-line from Interstate batteries. 12V 1.3AH AGM - Part #SLA105. Total $22 including shipping. Any AGM in that same physical size group should do.
To finish out the discusssion on the ODBII memory retainer - in my mind the electrical system of the truck is just wires that eventually all connect together. So you've got some sort of power source - either a 12V battery or a 12V power supply, that's getting connected to some very small gauge wires in your ODBII port, and those wires are eventually connecting to your main 12V power bus. How is that any better than just connecting a 12V Battery or Power Supply directly to the main power bus - I would argue it's worse because if you cause a short I would rather over-current is not traveling through very small gauge wiring in my ODBII port. I get why someone would build that product - in newer vehicles the cigarette lighters may be switched so the easiest way to get power to the system from inside the truck is through the ODBII port - I just think it's unneccessary and less than optimal for someone that knows what goes where under the hood.
#7
MBWorld Fanatic!
Thread Starter
Except the electrical systems are cars are not that simple since about 1998 on. (depending on the make and model)
There may be some amount of circuitry between the common battery hot and the various "+12V" lines in the car.
Example being, even our "non-switched" power outlets are in fact switched by a SAM, so they can be shut off when the battery is too low.
I am not sure which power runs to the OBD ports, but it s likely to be "filtered" side of any car that tries to isolate computer power from the noise starting, charging and large motor running side.
My concerns was if people knew that for some MB-Crazy reason, our cars did not like seeing power flowing in the ODB port.
I am not too worried about shorts, as the unit is powered by a 9V battery, and they will not light up much of anything.
There may be some amount of circuitry between the common battery hot and the various "+12V" lines in the car.
Example being, even our "non-switched" power outlets are in fact switched by a SAM, so they can be shut off when the battery is too low.
I am not sure which power runs to the OBD ports, but it s likely to be "filtered" side of any car that tries to isolate computer power from the noise starting, charging and large motor running side.
My concerns was if people knew that for some MB-Crazy reason, our cars did not like seeing power flowing in the ODB port.
I am not too worried about shorts, as the unit is powered by a 9V battery, and they will not light up much of anything.
#8
Member
Agree. Good luck with your project!
Next up for me is another round of transmission and gearbox fluid changes, new engine air filters and and a new fuel/water separator.
Next up for me is another round of transmission and gearbox fluid changes, new engine air filters and and a new fuel/water separator.
#9
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Thread Starter
The spin off cartridge will make things easier, and keeping the oil mist out of the intake will keep the whole intake system cleaner.
My goal is for the GL to be a forever vehicle.
#10
Super Member
I've only replaced my main battery, so far. Lost a few memory things, but no big deal. Didn't take much more than a few minutes to get them back. A couple of the windows (and the sun roof) didn't close/open via the one-touch... but it only takes 20 seconds to reset those.
If it was me and I was worried about losing more things with removing the little battery? Remove main battery, wrap a cloth around the positive lead and tape in place, connect the battery to the jump post under the hood with jumper cables, remove auz battery. Reverse procedure. I'm all in for buying tools - but sometimes it's easiest to just make do with what you already have lying around.
"Forever car"... I never quite got around to pulling the trigger to buying/installing this on my old '98 diesel Suburban, but check out the FS2500 Bypass Oil Filter system.
If it was me and I was worried about losing more things with removing the little battery? Remove main battery, wrap a cloth around the positive lead and tape in place, connect the battery to the jump post under the hood with jumper cables, remove auz battery. Reverse procedure. I'm all in for buying tools - but sometimes it's easiest to just make do with what you already have lying around.
"Forever car"... I never quite got around to pulling the trigger to buying/installing this on my old '98 diesel Suburban, but check out the FS2500 Bypass Oil Filter system.
#11
Super Member
You can get 1 micron spun polyester filters for very cheap. You can also get polypropylene housings (that's what you have on the RO filter under your kitchen sink) for cheap, too. See where I'm going with this? Pump oil up out the dipstick, through the filter, then back in the oil fill hole. Leave it running for an hour or so in your garage. Do this every few thousand miles.
I set it up but haven't tried it yet; I'm going to have Blackstone test the oil before and after polishing to see if my wacko scheme works.
#12
Super Member
Understand. If you are worried about instantaneous over-voltage by hooking a 12V power supply to your truck, then you could also attach any random 12V battery to the charging terminals. I just don't see a reason to spend money on a new gizmo for this procedure - you are a sophisticated wrencher and I know you have a bunch of reliable 12V DC sources you can choose from...
#13
MBWorld Fanatic!
Thread Starter
Incandescent bulbs have very low resistance below the current needed to light them.
A 12v 55w bulb effectively limits current to around 4A while providing very little voltage drop under when under an amp is drawn.
Due to a very slow start a few days ago, my wifes E350 is getting the new battery first.
Found one at Advanced Auto Parts for $195 less 25%
#14
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Join Date: Aug 2009
Location: Central Valley California
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2012 Mercedes GL350 2011 911 Carrera 4 Cabriolet 63' Thunderbird Sports Roadster
I checked Pep Boys for their Presidents sale and noticed they recommended the Bosch Premium 49-850BAGM for my 2012 GL350 but most interesting they would install for $60.00! I’m assuming they know the battery is under the passenger seat. Do you have any experience with their install at Pep Boys?
Additionally, if I replace both batteries can I replace the smaller battery under the hood myself and later have Pep Boys replace the main battery without any concern of having to reset deleted information ?
Additionally, if I replace both batteries can I replace the smaller battery under the hood myself and later have Pep Boys replace the main battery without any concern of having to reset deleted information ?
Last edited by KYBRIGGS82; 02-16-2019 at 09:26 PM.