Shunt/battery control module part-no

[T6_FunBus]

Could someone or a couple of people next time they are at their van please pop the bonnet and check the part number on the battery control module on their negative battery terminal and let me know please?

Any T6 from 2016 onward. If you could let me know they year as well that would be great thanks.

Thank you!

 

[La Dodgy Vita]

Late 2016 150BHP
Regards

 

[oldiebut goodie]

late 2018 204

 

[T6_FunBus]

Thanks guys this helps.

VW parts centre and my hungarian seller has told me for a T6 7E0915181K is replaced with 4K0915181A.

However, there appear to be later versions of 7E0915181 (L/M) with later dates on them.

The VW part is £187 direct from VW or over £200 from other retailers. Later 7E0915181 parts are also available from some suppliers for £80 new and listed as also fitting T6.

Seeing as I believe T6’s all use the same BCM, and the battery module is a fairly simple device (from what I have researched) using standard lin protocol and reporting the same parameter (battery current, temp etc) it seems odd that a later version would not fit.

I am hoping someone turns up with a T6 with a later revision part so we can clear this up, may also help someone in future.

Also the later part is showing as fitting multiple vw models and years as attached.

 

[Alster]

2021 T6.1 199

 

[T6_FunBus]

Thanks so much guys for the help. So I ‘think’ this confirms that 2016-2019 t6 uses the K revision part no, and from L it is t6.1.

If t6.1 uses a different bcm then I guess its possible the part is not compatible, or, that part will work but it is only listed on parts system under 6.1, so neither dealer or aftermarket can recommend it.

Hmmm what to do!

 

[Lightrofit]

4K0 915 181 A is the correct current part number for the battery terminal sensor from your VIN (from our messages)

 

[Alster]

Has anyone looked inside one - I assumed it was just a shunt with no electronics.

 

[T6_FunBus]

Thanks @Lightrofit.

@Alster thats my thought, but I’m not sure how I can clarify.

They do not appear to be coded to the van - swap in and out, that is unless they have some coding from factory for a specific vehicle module perhaps??

I even found Hella do a generic IBS that looks absolutely identical and communicates on lin and feeds back standard parameters for stop start vehicles.

The problem is, the part no with L onwards on the end as shown on this thread was when the T6 was out of production and listed from 2020, so the dealer or aftermarket will not show the part for a t6 even though it ‘may’ work fine.

There is a difference is £100 between part no’s (6.1 shunt / ibs and even later t6 replacement part).

If I was 100% sure it will fix my errors I’d bite the bullet and spend the £186 with VW, but I’m not, so I’d rather but a cheaper compatible part. But, if I cannot identify one works with a t6 then its going to have to be the more expensive one.

I am also intrigued though, as I’ve had many similar experiences with my audi and other vehicles. A part no or no part no is listed in systems for my model, but a similar or base model part is identical and works just fine.

If I could find an alternative it would be useful for others who may have the same challenge in the future. Will have to have a think.

Here is the hella version, they look identical, have a 12v feed and lin coms wire. Only difference in models appear to be which side the terminal is and configuration to help mounting…

IBS sensors - Intelligent battery sensors | HELLA

IBS sensors | Available for 12 V ✓ Support for numerous battery models ✓ HELLA commercial sensors are a 100% replacement for the original component ✓

www.hella.com

I honestly think VW are charging £200 for something you could get for £50 that would work.

I would try it, but as I said I will be dealing with two unknowns (whether sensor is compatible and whether it is the part at fault). So I don’t think I can take the risk as I wouldn’t know either way which was true if the part did not work.

 

[Lightrofit]

The L and N parts are specific to the T6.1 and with how the electronics differ, there will be a reason that the T6 and T6.1 didn't share the superseded part

Also, looking at the wiring diagrams, the T6 LIN goes directly to the BCM, which would make sense as the gateway and battery regulation control module is built into it.

On the T6.1 the LIN goes to the Gateway, which is a separate module and is also the battery regulation control module.

So with that in mind, yes it may work as it's just a sub-module for the reg control module but then again if they aren't using the same part on both vans then there is usually a reason

 

[Alster]

Having googled it it appears that it’s more than just a mechanical shunt so as @Lightrofit says it’s probably not compatible

 

[roadtripper]

So this intrigued me as I'd always assumed it was a straight shunt, but thinking about it that would likely not work well as you are trying to measure millivolts in an electrically harsh environment, the amount of noise you'd get on the wires could swamp the measurements. Much better to measure it in a screened environment as close as possible to the shunt and send the data elsewhere.

Looking up the LIN protocol it's a simpler and cheaper to implement alternative to CAN for non critical devices.

I suspect the difference might be down to different baud rates with different generations of ECUs.

The note in the protocol that you can do LIN over DC power cabling so you can piggy back onto power cables and not run any data lines at all is intriguing, especially given that others have found odd pulses on what would normally be "plain" power cables.

 

[T6_FunBus]

I just wanted to add, that there are other modules for example 4K0915181 that has Hardware version H03 and Software Version 1050. Part number 4K0915181A also has H03 and SW 1050.

The T6 modules above all also have HWV H03 and SWV 1050.

I can see that T6.1 module posted is the first modification after 7E0 915 181 K, with the 'L' letter, which from investigating is the identification for a modification of the part.

Seeing as 7E0 915 181 L has HWV H03 BUT SWV 1051, it would seem to suggest the software version does not reset along with the part modification, but the t6.1 part does indeed have a later software version.

This could this mean any Battery module with H03 and SW 1050 would work? Maybe...

I have found a cheap audi A3 part no 4K0915181, HW03 SW1050, but its been ripped out and who knows what may be up with it, so rather than risk connecting that to my van, I think I am going to bite the bullet, hand over the 180 odd to VW, and hope that a somewhat educated guess with what I have found out through troubleshooting and help from others that the battery module is the culprit!

Cheers,

 

[Bigsidavies]

Is there no one local (or local VW indi) that can swap a known good one with yours in an attempt to prove that this is where the fault lies?

 

[Lightrofit]

The last letter (and sometimes the colour code) aren't always for superseded/upgraded parts. They can also signify specific functionality differences and even vehicle compatibility too.

A good example of this is DRL/headlight control modules. Different letters specify which vehicle they are for so even though the core part number is the same, the letter means they can't be swapped/used on different vehicles.

With HW/SW numbers. This can have a huge impact too. For example, Audi A4 B8 and A6 C7 (2 cars that share LOADS of parts that can be swapped between them) share identical looking door control modules and even the part numbers are super close and plug pin configuration is the same but the HW/SW numbers are different and if you plug in an A6 door module into an A4 it screws the entire A4 CAN network and the car is a brick.

 

[T6_FunBus]

Is there no one local (or local VW indi) that can swap a known good one with yours in an attempt to prove that this is where the fault lies?

I haven’t found one, I did think about it but also a but reluctant to ask someone to pull their van apart for me

The last letter (and sometimes the colour code) aren't always for superseded/upgraded parts. They can also signify specific functionality differences and even vehicle compatibility too.

A good example of this is DRL/headlight control modules. Different letters specify which vehicle they are for so even though the core part number is the same, the letter means they can't be swapped/used on different vehicles.

With HW/SW numbers. This can have a huge impact too. For example, Audi A4 B8 and A6 C7 (2 cars that share LOADS of parts that can be swapped between them) share identical looking door control modules and even the part numbers are super close and plug pin configuration is the same but the HW/SW numbers are different and if you plug in an A6 door module into an A4 it screws the entire A4 CAN network and the car is a brick.

Lol that’s enough to scare me off.

I have done similar before though, example a door control module for a w209 mercedes, part number was for a c209 and it had an earlier software revision, everything worked apart from the power fold mirrors on lock as it needed to be coded.

 

[T6_FunBus]

Just coming back to this.

So after replacing this module I had the same errors, my problem ended up being the green/yellow wire being broken (somewhere) between BCM, this battery module and the alternator.

I ended up rewiring all, and fitted a new LIN wire from BCM, to alternator, to battery module. My alternator, stop start, and battery monitoring control module errors then went away.

I have however noticed the red wire has a split in it (from vibrations) near the connector, so likely also has an intermittent connection.

I am currently troubleshooting a few errors:

00446 - Feature limitation due to insufficient voltage
P16CB00 - Heater support pump supply voltage

There has also been a long time ago a ‘reference voltage’ error. I have not seen this for a long time.

With the heater pump, I have had the pump replaced with a genuine VW item, I have also fully rewired and tried a new plug / connector but have the same issue.

Red battery light occasionally comes up on dash, so I am now wondering if the supply voltage error to the pump, is not a pump or pump wiring issue at all, but another problem…

I don’t believe the red wire on the above module will fix this, but then, I do not really know what the consequences are of it being damaged either are??

 

[oldiebut goodie]

There appears to several cases of broken wires cropping up, I wonder why. Poor routing or poor quality cabling?

 

[T6_FunBus]

There appears to several cases of broken wires cropping up, I wonder why. Poor routing or poor quality cabling?

Poor routing and or both I guess.

It seems I’m not the only one, and broken / worn wires are common on the T6 as they age. I’m not surprised to be honest, there are a lot of exposed wires and those that are in the conduits are routed in such a way they are pulled very tightly in many directors, and clamped around the engine bay.

Typical example being the alternator LIN wire that I am not the only one to fall foul of.

That and, well, it’s an Ex AA van, so people splicing into electrical wires to fit other stuff. 99% of the AA wiring is removed. There are still two curious wires though, one spliced into ECU ground wire and another into the knock sensor… Neither of those appear to be causing issues, since if the ECU had a poor ground one would assume it would die and so would the van. No knock sensor errors either.

The other problem I guess are garages and work being done on the van. Looms need to be unclipped and pulled out the way to allow access to replace parts like clutch / flywheel, then pulled back or routed properly and electrical plugs clipped back in.

When the last garage replaced the pump, they said whoever did the cambelt had reconnected the pump by pulling the wire round the back of an engine like the wrong way, causing it to rub…

But back to the conduit under the engine bay, the wires are thin, not wrapped well, and not well protected from water ingress and elements, especially as it is just sat on the bottom of the sump behind the bumper grills. So easy to damage over time and for water to also get in.

I honestly would never buy another VW or transporter after the horrible wiring and electrical experience I have had. And given it is not just me with such issues, it seems the wiring and electrical system as a whole is not very robust as they age.

I guess some people are lucky, some are not. Shame as I had two years of perfect reliability before the recent stream of problems over the past 6 months.

 

[roadtripper]

There appears to several cases of broken wires cropping up, I wonder why. Poor routing or poor quality cabling?

It does seem odd that it's always the LIN wire, you'd think it would be others with similar routing or from the same supply chain.