Battery failed - can I replace it without VCDS?

My battery has been getting weaker over the past week. Thinking that I was taking it for too short of trips because of the lock down - I put it on a trickle charger overnight and it started without hesitation. I tried starting it this AM and it barely turned over. This battery went down hill quickly.

I need to replace the battery but I don't have VCDS. I can get a ride to walmart/ auto zone and buy a replacement battery but I thought that you have to put the code of the battery into VCDS?

Options?

I got my battery from the dealer thinking the same thing, that they would code it. They didn't, they just slapped it in. I found out later when I logged in with OBDeleven and I did it myself.

I’ve never heard of a TDI that has the battery management system. I believe you can just swap it without VCDS.


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You should buy a obdeleven, it's a cheap investment.

Subscribed.

I'm still learning about these newer models, but I just bought a new battery for my '04. No coding required, and the last one was VW that lasted 9 years!

Used to also have an '06 mk5, no coding required.

This new batt I paid around $150 at the dealer (including tax), I believe the guy said 1 year full warranty, 5 prorated.

i just swapped mines in 15 golf , never heard about coding

Some sub models do have a battery management system that require recoding for the new battery as the car will use a different charging strategy based on battery age. I do not believe any TDI has the battery management system.


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I changed my battery and it does need coded with vcds. Will the car still work without vcds? Yes. Will this shorten the battery life due to altered charging patterns? Likely yes.

Did you code it because you changed it to AGM, like your signature says? ...that's different.

Neither of my 2015 have AGM batteries.

If you did have to code something, could you please let us know what you coded?

pedroYUL said:

Did you code it because you changed it to AGM, like your signature says? ...that's different.

Neither of my 2015 have AGM batteries.

If you did have to code something, could you please let us know what you coded?

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Yes I had to change the battery type. Word around the camp fire is as a battery ages the control modul changes how it charges the dying battery. In order to reset the system you go into the battery charging modul and change the serial number of the installed battery. This lets the system know to clear stored data on the old battery. Obviously this is just what I've read and how I choose to handle my car. Research the process and see what you wana do.

http://wiki.ross-tech.com/wiki/index.php/Battery_Replacement

Also you can look at the Mk7 vw forums for other or more info.

My wife's 2015 TDI has a battery management system, and I did enter the code with VCDS when I swapped in a new one for her.

So yes, battery management does exist on a TDI. On a 2015 at least.

If you're swapping in a battery that is the same battery chemistry (AGM), and same Ah rating, it probably won't make any difference if you don't enter the code. The battery should behave roughly the way the computer expects it to. If anything is different, then coding is more important.

Mike_04GolfTDI said:

My wife's 2015 TDI has a battery management system, and I did enter the code with VCDS when I swapped in a new one for her.

So yes, battery management does exist on a TDI. On a 2015 at least.

If you're swapping in a battery that is the same battery chemistry (AGM), and same Ah rating, it probably won't make any difference if you don't enter the code. The battery should behave roughly the way the computer expects it to. If anything is different, then coding is more important.

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My 15 Golf SEL doesn’t have it. Do you have the additional wiring coming off the negative battery cable? If not it doesn’t have BMS.


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kdawg89 said:

My 15 Golf SEL doesn’t have it. Do you have the additional wiring coming off the negative battery cable? If not it doesn’t have BMS.

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It appears to have it, meaning VCDS finds the battery management module and allows you to change the coding from the original battery to the new battery.

Before I changed it, the module did contain the coding from the original battery, so VW entered that information when the car was manufactured.

Maybe some cars have it, and some don't, depending on features. The car I did it on is a 2015 Golf TDI Comfortline with DSG and convenience package. It's a Canadian model.

My understanding is that all cars have have the info in the computer and you can see it and change it, but unless you have start stop tech it doesn’t actually do anything. Either way I would also code mine when I replace it but I’m pretty sure on a TDI if you don’t have access to VCDS it wouldn’t actually matter.


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kdawg89 said:

My understanding is that all cars have have the info in the computer and you can see it and change it, but unless you have start stop tech it doesn’t actually do anything. Either way I would also code mine when I replace it but I’m pretty sure on a TDI if you don’t have access to VCDS it wouldn’t actually matter.


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What do you mean by "start stop tech"?

bigb said:

What do you mean by "start stop tech"?

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The gas cars have start stop technology. Turns engine off at stop lights etc.


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kdawg89 said:

The gas cars have start stop technology. Turns engine off at stop lights etc.


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ah got it

When I coded mine I just changed the number 1 digit, I don't think there was any more options so it probably doesn't do anything more than keep a record of battery replacement on mine anyway

Mike and kdawg-
how were you able to tell if your '15 had the management system (or not)? Did you need VCDS to find out if you had the battery management system installed or is there something to look for under the hood?

I think this is where some of confusion is coming from.

All 2015 TDI didn't come with start stop and come with standard FLA batteries.

If you "upgrade" to an AGM battery then you'd need coding.

sands80 said:

Mike and kdawg-
how were you able to tell if your '15 had the management system (or not)? Did you need VCDS to find out if you had the battery management system installed or is there something to look for under the hood?
I think this is where some of confusion is coming from.

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I used this guide to do the battery coding with VCDS.

http://wiki.ross-tech.com/wiki/index.php/Battery_Replacement

I was able to successfully do the coding, but whether or not it was strictly necessary on the 2015 TDI, I don’t know. I just did it because I have VCDS, and the internet says to do it.

Yeah, I wouldn’t buy VCDS or OBDELEVEN just to replace the battery although it is worth owning one. I’m pretty confident you don’t need to worry about it as generally it is only cars with start stop tech the require battery coding, and the TDI doesn’t have the extra battery management wiring required. You can see a good explanation of it on this site.


https://www.samarins.com/glossary/battery-sensor.html

Bat basically the TDIs do not have the current sensor required for the car to do things like variable output charging. And variable output charging is exactly why you would code the battery to the car. It can then adjust charging voltage based on battery chemistry or put out more or less power to the battery depending on age of the battery, electrical load, battery charge state (which varies a lot on start stop cars because they run HVAC, radio, etc even with the engine off) and which is why these systems exist.


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I was tracking something else using VCDS in my 2015 GSW, and went ahead and checked for the batt module...there is none, exactly like kdawg89 says.

kdawg89 said:

I’ve never heard of a TDI that has the battery management system. I believe you can just swap it without VCDS.


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I did. It had multiple dash lights come on. They went out after a few feet of movement. No codes, all good. Ive seen others state the same.