8.5R Gremlins

[AHG]

Hat can explain the sensitivity 

In my previous car (S3 ‘18) and in the Tiguan (‘19) Start/Stop is original set to stop turning the engine off when stopping only when battery voltage is below 7.6V, which means that until then it can start the car without any risk or issue.

 

So it is very plausible that a battery has enough o start the engine but low enough to be noticed by other modules and throw a flag (e.g. 10V).

 

If past generations Golfs had voltage step downs (to 5 or 3V) they wouldn’t be as sensitive because even at 7.6V they would get their full requirement.

[dv52]

1 hour ago, mahalo said:

 The battery monitor(J367)  is just connected  directly to the battery so will just measure a straight battery voltage drop across the battery. 

@mahalo: Hmm......... not really!! Lots of folk reading the VW wiring diagram totally underestimate the role of J367 (I guess because it looks like a very simple module). However, that misunderstanding is far from the truth  - J367 is actually the principal information provider for the car's Energy Management System (EMS) and it plays a key role in the decision matrix for the operation of the Start Stop facility ( and it certainly is NOT "just measuring a straight battery voltage" - no offense intended)

 

The primary role of J367 is to measure in real time the following  battery values:
- Battery temperature
- Battery voltage
- Charging current
The battery temperature is measured using a look-up table and the ambient temperature. It also allows the duration of the battery load to be determined. The data obtained allows the charge regulation as well as the charge voltage to be adapted to the charge and operating state of the battery. The aim is to increase the availability of the start/stop system with the detailed data evaluation of the starter battery.

 

A schematic of the internal smarts of J367 looks like this:

 

Notice the "Shunt" in the schematic- this is special stabilized resistor (low ohm value) that is used to measure and record every milli-amp of electrical current that flows into and out-of the battery over its complete life cycle. This history file is used by the EMS to customize the charging profile (taking account of battery age) so as to optimize battery performance and battery longevity. That's why its vitally important on cars that have a J367 module to ALWAYS ensure that using external chargers and jump-batteries is done correctly - else the History file is corrupted!!!

 The extended role of J367 in the proper functioning of the car's EMS is also why it's important to tell J533 (Gateway module) whenever the battery is changed because any change in battery details alters the optimal charging profile and the EMS needs to reset the battery history data for the new battery! Maintenance of the newer technology EHB and AGM batteries is more demanding than the normal flooded-cell batteries!!

 

As I said - J367 is a much undervalued module!!

 

Don

[blizzard60]

3 hours ago, mahalo said:

Thanks for this - I have managed to find the Golf Mk 8  wiring diagrams and yes it looks like they all being fed 12v. J329 regulates the power on SC58. The battery monitor(J367)  is just connected  directly to the battery so will just measure a straight battery voltage drop across the battery.  

I wonder how J519 and J533 react if the battery voltage drops.

 

On the other hand, compared to @dv52's comments on the J367, J329 is a simple old school relay. It's the Terminal 15 relay. It's not regulating the voltage.

 

[dv52]

8 hours ago, blizzard60 said:

 

On the other hand, compared to @dv52's comments on the J367, J329 is a simple old school relay. It's the Terminal 15 relay. It's not regulating the voltage.

Haha........ yes indeed!! I too have never understood why the deities on the VW mother-ship choose to call these "simple old school" relays modules! Other than the electro-mechanical parts in the relay, the only electronic component in J329 is the blocking diode (the rectangle across the relay-coil shown on your diagram on the housing). One diode is hardly a good reason to call this a module!!

 

Forgive the pedant in me and I do agree with your words "It's not regulating the voltage" -but it really depends on how "regulating" is defined. Like J367, the simple relay, J329 is also pivotal to the car's operation since it is the primary mechanism for generating the entire T15 rail voltage that is used by lots of components.

 

Don't get me wrong, it's true that the actual value of the T15 voltage is "not regulated" by the relay because "T15" is simply a switched form of the hard battery voltage (i.e. T30 volts) - however, the existence of the T15 rail voltage is regulated by J329 (IMO, of course)!!

 

No offense intended - as I said, I'm a proud  (strange?) pedant where wiring diagrams are concerned and lots is revealed when reading between the lines!!

Don  

[AHG]

So, the T15 just gives the car accessories power for 15min after turning the engine off, and the. Turns it off when the 15min are up ?

That would make sense as to why some parameters (like Recirculating Air) reset only if you don’t restart the car within 15min 🙂

[blizzard60]

1 hour ago, AHG said:

So, the T15 just gives the car accessories power for 15min after turning the engine off, and the. Turns it off when the 15min are up ?

That would make sense as to why some parameters (like Recirculating Air) reset only if you don’t restart the car within 15min 🙂

 

Nah, Terminal 15 has nothing to do with 15 minutes. It just means it's switched on ignition as opposed to Terminal 30 which is constant/always on.

 

Modern cars *may* turn off the ignition after a certain time, but that's not why it's called "Terminal 15".

[blizzard60]

1 hour ago, dv52 said:

Haha........ yes indeed!! I too have never understood why the deities on the VW mother-ship choose to call these "simple old school" relays modules! Other than the electro-mechanical parts in the relay, the only electronic component in J329 is the blocking diode (the rectangle across the relay-coil shown on your diagram on the housing). One diode is hardly a good reason to call this a module!!

 

Forgive the pedant in me and I do agree with your words "It's not regulating the voltage" -but it really depends on how "regulating" is defined. Like J367, the simple relay, J329 is also pivotal to the car's operation since it is the primary mechanism for generating the entire T15 rail voltage that is used by lots of components.

 

Don't get me wrong, it's true that the actual value of the T15 voltage is "not regulated" by the relay because "T15" is simply a switched form of the hard battery voltage (i.e. T30 volts) - however, the existence of the T15 rail voltage is regulated by J329 (IMO, of course)!!

 

No offense intended - as I said, I'm a proud  (strange?) pedant where wiring diagrams are concerned and lots is revealed when reading between the lines!!

Don  

 

Firstly, absolutely no offence taken in any way, I LOVE it in fact! We ARE risking being booted to a back room for maybe taking this off topic, and anywhere but the MK8 sub scares the bejesus out of me 😜

 

Hmmmm, you are wading into linguistic opinions and here, and I must defer to people WAY smarter than I! So, I used google AI to better define a "voltage regulator" than I could. Here's what they said:

 

"A voltage regulator is a circuit or device designed to maintain a stable, fixed output voltage despite variations in input voltage, load conditions, or temperature. It essentially acts as a "stabilizer" for the power supply, ensuring a consistent voltage level for the connected device or circuit."

 

I think it is fair to say J329 does not do that?

 

IMHO, what J329 does is SWITCH the voltage. On or off. As all relays do. At one past life, I was a physics student up to the undergraduate level. Admittedly my memory is NOT what it once was, but I'm going to say that I never heard a prof say a relay "regulated voltage".

[dv52]

1 hour ago, blizzard60 said:

 At one past life, I was a physics student up to the undergraduate level.

Arrhhh........... a man (woman?) after my own heart - I absolutely adore Physics! It's the language of the divine -if I believed in a deity, which I don't!!! 

 

And I agree - way too off-topic to risk the devastating wrath of the moderators!! 😀

 

Don

[dv52]

3 hours ago, AHG said:

So, the T15 just gives the car accessories power for 15min after turning the engine off, and the. Turns it off when the 15min are up ?

That would make sense as to why some parameters (like Recirculating Air) reset only if you don’t restart the car within 15min 🙂

To add to @blizzard60 sage response, the nomenclature that the car industry uses for these voltages is defined in DIN 72552. It's an industry standard (originally developed by Bosch) for labeling the electric terminals in automotive wiring

 

The 3 x main voltage labels are:

• Terminal 30 (T30) = direct battery volts (always live)
• Terminal 15 (T15) = battery volts that is only live when ignition is switched-ON
• Terminal 31 (T 31) = earth

You can read the rest of the Terminal numbers -  HERE

 

Don

PS: it's interesting (to me, at least) that the designation for ignition switched volts = half x direct battery volts!!

[blizzard60]

1 hour ago, dv52 said:

 DIN 72552.

You can read the rest of the Terminal numbers -  HERE

Hey, I did not know this DIN standard!! I mean, I know the nomenclature, the rules of the standard (not all of them), but not the #, so have never looked it up before. Thank you! Now I have a Wikipedia page to read tonight, brilliant!

[blizzard60]

2 hours ago, dv52 said:

Arrhhh........... a man (woman?) after my own heart - I absolutely adore Physics! It's the language of the divine -if I believed in a deity, which I don't!!! 

 

And I agree - way too off-topic to risk the devastating wrath of the moderators!! 😀

 

Don

Haha, exactly! Scary @Booth11 might come along 😝

 

I am, indeed, of the Y chromosome variety!

[Booth11]

@blizzard60, @dv52, @AHG

I’m of gracious mind today (and as you know am not remotely scary), so there’ll be no kicking you off the thread into the diabolical depths of the forum abyss, especially as the conversation has evolved from a post which was relevant to the thread topic (well, partially).  Indeed it is very educational reading for all of us, even those of us (self included) whose knowledge of such is next to non existent. Plus the good news is that whilst there isn’t much being reported in the way of actual gremlins (a good thing), we may as well put that this space to related learning.  
 

Of course, if you wish to have a thread devoted solely to the topic of the wiring and inner electrical gubbins of the mk8/8.5R, then feel free to start a thread where you can post and discuss anything in that area to your hearts content.  😊

[MrBlobby]

Can anyone help me please. The dealer who collected my car after putting in a rejection email said they have done a few road tests in the car and SURPRISE SURPRISE can not replicate the issues and have relayed that to the broker, thus “keen” to get the car delivered back to me… Idiots are probably driving it like a granny. 

 

I do not want the car back, on day one I have the issue with the car and it’s been consistently there when on a sprinted drive.. the issue I’m having having is the gearbox confusion issue where on a sprinted drive particularly in special/race model the gearbox box in manual the paddle shifters don’t work… it’s been reported in here a few times by members and VW Milton Keynes are aware of the issue and are working on an update.. software update/shifters to replace from previous comments here.

 

luckily I’ve taken a few videos of the car playing up and the shifters not working in manual mode.. just wondering if anyone has been in same situation before, so do I now contact my finance company, complain to VW to put the pressure on the dealership.. The gearbox feels sluggish as the weeks have gone by and I’m not happy with it.

 

Thank you 

[Booth11]

25 minutes ago, MrBlobby said:

Can anyone help me please. The dealer who collected my car after putting in a rejection email said they have done a few road tests in the car and SURPRISE SURPRISE can not replicate the issues and have relayed that to the broker, thus “keen” to get the car delivered back to me… Idiots are probably driving it like a granny. 

 

I do not want the car back, on day one I have the issue with the car and it’s been consistently there when on a sprinted drive.. the issue I’m having having is the gearbox confusion issue where on a sprinted drive particularly in special/race model the gearbox box in manual the paddle shifters don’t work… it’s been reported in here a few times by members and VW Milton Keynes are aware of the issue and are working on an update.. software update/shifters to replace from previous comments here.

 

luckily I’ve taken a few videos of the car playing up and the shifters not working in manual mode.. just wondering if anyone has been in same situation before, so do I now contact my finance company, complain to VW to put the pressure on the dealership.. The gearbox feels sluggish as the weeks have gone by and I’m not happy with it.

 

Thank you 

I think the usual practice prior to accepting rejection of a car, is that they are afforded the opportunity to ‘fix’ the issue, before rejection is pursued.  From the information shared here, it would appear that VW are aware of the paddle problem and are working on a fix, although the timescale for this seems unknown to us.  Of course this approach does mean that the dealership has to acknowledge and accept the issue exists, and even though they themselves have not replicated it, the fact you have presented video evidence of the fault and it’s a known issue, should surely be acceptable as such?
 

What, if anything, have they said to you about any forthcoming fix for the paddle problem?    

[MrBlobby]

30 minutes ago, Booth11 said:

I think the usual practice prior to accepting rejection of a car, is that they are afforded the opportunity to ‘fix’ the issue, before rejection is pursued.  From the information shared here, it would appear that VW are aware of the paddle problem and are working on a fix, although the timescale for this seems unknown to us.  Of course this approach does mean that the dealership has to acknowledge and accept the issue exists, and even though they themselves have not replicated it, the fact you have presented video evidence of the fault and it’s a known issue, should surely be acceptable as such?
 

What, if anything, have they said to you about any forthcoming fix for the paddle problem?    

I sent them the rejection notice within the 30 days meaning I don’t have to give them the opportunity to fix the car, after 30 days they are allowed one attempt right?

 

I haven’t been communicating directly with the dealership, it’s all going through the car broker I used but what I’m going to do now is forward the videos. They haven’t asked me for these yet, just keen to paw the car back to me which I’ve lost faith in, I’ve driven a few MK8’s before and it’s clunky it is hard to explain but it just does not feel crisp at all.