Hello to all,

 

This post is for anyone who was wondering if the old method for turning off start-stop works on the Mk IV.

 

TL;DR IT WORKS.

 

I've owned a 2021 Octavia Mk IV for about a year now and it is my preference to start the car with the system disabled. I have owned other Skodas previously and was very satisfied to use an aftermarket memory module on the physical start-stop system switch where available. Other members who own a Mk IV will know that it is not possible to use this approach on our cars because there is no physical switch.

 

The times that I forget to turn the system off before I start driving frustrate me intensely, because the system decides to cut the engine at the most inopportune time (in my opinion). It can only be disabled by using the touch screen. I try to avoid using the touchscreen when I'm already in traffic because I think it's pretty dangerous.

 

I had been patiently waiting for better minds to work out the coding required to permanently disable the start-stop system, but today I had enough. I wanted to see if the old method of disconnecting the little black plug from the negative battery terminal worked. I had not been able to find any reports of people trying this method on the Mk IV so far, so I thought I might as well try it and post here with the result.

 

After reading page 30 and page 65 of the Mk IV electrical system service manual, I disconnected the plug from the negative battery terminal and went for a drive. The plug on mine was orientated differently to the diagram but it was easy to tell that it was the same plug.

 

It worked exactly as I expected it would. The start-stop system was disabled without any input from me. I went for a few more drives to see if the rest of the car's functions were affected by disconnecting the module. I can say that, as far as I can tell, none of the car's other functions seem to be affected.

 

The message to inform you of the start-stop system error isn't even annoying on this car! You just get a momentary notification on the left side of the virtual cockpit the first time that you come to a stop during that power cycle of the ignition and then it goes away! It doesn't bother you again for the rest of the drive. It doesn't even play that annoying bong sound that every other error message or fault code plays. You will find the error message under vehicle information on the infotainment unit, but for that you'd have to use the touchscreen 😁

 

For me, this is a vast improvement over cutting the engine right when I don't want it to in the event that I've forgotten to use the touchscreen to disable it.

 

Now, it's important to note that the service manual states that module J367 also controls the auxiliary heating, so if your car is fitted with that option then this method may not be for you. My car doesn't have that option and it's not available in my region, so I can't say for sure. It also states that an entry is made in the event memory for every time that the system produces an error. I don't care about this because since the last software update, my car throws fault codes for emergency assist and travel assist multiple times every second drive or so. It probably records so many errors it doesn't matter. Hopefully software version 1896 fixes some of those when I get it. It's a good thing I'm very tolerant of the software bugs, because I do really like the car otherwise.

 

I hope that this post assists anyone who wanted to try this, but wasn't game to go in blind.

I think there is a topic on Briskoda where it was confirmed that unplugging the start/stop cable from the battery causes BMS (battery management system) failing to optimally charge the battery. 

I can't really say it bothers me to be honest. 

The lane keep assist however......that always gets switched off.

 

I've been looking for this!  Stopstart is a stupid system - as you say it chooses the worst moments to cut out, usually just as your about to go for a gap on a roundabout or something.

 

Can you post some more details on how to do this?

1 hour ago, Bobe said:

I've been looking for this!  Stopstart is a stupid system - as you say it chooses the worst moments to cut out, usually just as your about to go for a gap on a roundabout or something.

 

Can you post some more details on how to do this?

 

In manual cars it only cuts out when you are stopped, in neutral and with the clutch up.

I don't see how on a manual car it could cause that.

 

On an auto I guess it could be more annoying.

yes it is an auto

What are the criteria for an auto?

Car isn't moving and in neutral with the handbrake on?

 

It can't just be a car in drive and not moving surely?

 

never had a problem with using mine on last car and it was a auto.

Yes - if you are not moving and in D

 

So if you pull up to a junction and stop even just for a moment, the engine dies.  You then floor it to get into a gap in the traffic and you get a full 1-2 second wait before it lurches into action.  It is most irritating in busy city driving.

 

I had the system on my last two cars, one was petrol and manual (Golf GTI) that was fine, the other was petrol and DSG (VW Arteon) and that was fine too, however I think the TDI Diesel engines take a fraction longer to fire up (current car is VRS Diesel) only my observation though and someone technical may correct me on this.

 

8 minutes ago, cheezemonkhai said:

What are the criteria for an auto?

Car isn't moving and in neutral with the handbrake on?

 

It can't just be a car in drive and not moving surely?

 

 

59 minutes ago, Bobe said:

Yes - if you are not moving and in D

 

So if you pull up to a junction and stop even just for a moment, the engine dies.  You then floor it to get into a gap in the traffic and you get a full 1-2 second wait before it lurches into action.  It is most irritating in busy city driving.

 

I had the system on my last two cars, one was petrol and manual (Golf GTI) that was fine, the other was petrol and DSG (VW Arteon) and that was fine too, however I think the TDI Diesel engines take a fraction longer to fire up (current car is VRS Diesel) only my observation though and someone technical may correct me on this.

 

 

I can see why that would be infuriating…

Are you pressing the brake pedal firmly or lightly? 

 

Never had any issues of this on my Mk3, unless my foot is firmly on the brake pedal, if I'm holding it down lightly it doesn't do it.

Lots of generalising going on here.

There are TDI's and DSG's that cut the engine before you actually get to a holt and without the brake pedal being pushed.

But then there are different sizes of TSI engines  1.0, 1.4, 1.5, 2.0 and mild hybrids and plug ins and different DSG's as in dry or wet clutch. 

 

Plenty drive various types and adjust to how they behave and can just press the Stop / Start button as and when the location suits, or know how to just feather the accelerator coming to a halt and not have the engine stop before coming to a stop.  Before actually touch the brake pedal and having the engine cut and have autohold on or not. 

Edited 6 June, 20223 yr by roottoot

On 05/06/2022 at 17:49, GreenlineIIEstate said:

The lane keep assist however......that always gets switched off.

 

 

If I was at all religious I would say lane assist is proof that satan exists 😁

13 hours ago, roottoot said:

Lots of generalising going on here.

There are TDI's and DSG's that cut the engine before you actually get to a holt and without the brake pedal being pushed.

But then there are different sizes of TSI engines  1.0, 1.4, 1.5, 2.0 and mild hybrids and plug ins and different DSG's as in dry or wet clutch. 

 

Plenty drive various types and adjust to how they behave and can just press the Stop / Start button as and when the location suits, or know how to just feather the accelerator coming to a halt and not have the engine stop before coming to a stop.  Before actually touch the brake pedal and having the engine cut and have autohold on or not. 

 

Fair points.  Few points on the mk 4 octavia - 

 

the stop start button is buried in a touch screen menu - not as instantly accessible as in the old models.

the engine cuts before you reach a complete halt - almost as if the car is predicting your next move.

 

back to the original post by @rickhoy615 - can someone point me to an instructional on how to switch off said system?

3 minutes ago, Bobe said:

 

back to the original post by @rickhoy615 - can someone point me to an instructional on how to switch off said system?

I think there is only one connector on the negative terminal on the battery. You can't miss it.

Joined to say that I also dislike auto start stop and I like not having to think about turning it off every time. Can confirm that the switch to turn it off is buried in the touchscreen menu on this car. Even if you have put the shortcut to turn it off on your notification panel, it's a two step process to swipe down then press the shortcut. I've found the gesture to swipe down and open the notification panel is horrendously unreliable depending on how soon you want to open the panel after starting the car. Infuriating!

 

Just tried this out. Works great!

 

On 07/06/2022 at 16:52, Bobe said:

back to the original post by @rickhoy615 - can someone point me to an instructional on how to switch off said system?

Here's a link to an article with pictures. See method 1: disconnect voltage sensor. How to permanently disable Auto Start-Stop on VW Tiguan (wheelsjoint.com). The article is for a Tiguan, but the battery looks exactly the same on my Octavia.

 

On 06/06/2022 at 00:20, TheUltraRunner said:

I think there is a topic on Briskoda where it was confirmed that unplugging the start/stop cable from the battery causes BMS (battery management system) failing to optimally charge the battery. 

Do you happen to have the source for that? I can see why it would be an issue for hybrid vehicles that have a complicated BMS, but I don't see a problem for a regular petrol/diesel car.

1 hour ago, manfred92806 said:

it's a two step process to swipe down then press the shortcut. I've found the gesture to swipe down and open the notification panel is horrendously unreliable depending on how soon you want to open the panel after starting the car. Infuriating!

You know you can also press the physical Set button and then turn off the stop/start system? Much easier than swipe down.

 

Will try to find that source.

1 hour ago, manfred92806 said:

Do you happen to have the source for that? I can see why it would be an issue for hybrid vehicles that have a complicated BMS, but I don't see a problem for a regular petrol/diesel car.

https://www.vwroc.com/forums/topic/37047-disconnecting-stopstart-system/

It's not from Briskoda. But from another vw forum.

11 hours ago, TheUltraRunner said:

You know you can also press the physical Set button and then turn off the stop/start system? Much easier than swipe down.

Thank you for posting this! I honestly had not put it together that THIS was the quickest way to achieve the desired result. The physical buttons have the effect of returning straight to the previous thing you were doing if you haven't got more than one level deep in the menus and you press the button a second time.

 

There's three ways to turn off auto start stop on this damn car.

1. Press SET ➡️ tap Start/stop ➡️ Press SET to return to what you were doing
2. If you have the shortcut on your notification panel, swipe down on any screen to open the notification panel ➡️ tap the shortcut for Start/stop
3. Open the main menu ➡️ tap vehicle settings ➡️ tap status on the right side of the screen ➡️ tap Start/stop

I blame Skoda. This is an awful UI/UX decision. I had looked at the SET menu many times, but always passed over it because I had learnt the notification panel method from the dealer. There should not be more than one procedure for dealing with a function like this.

 

The thread on VWROC is not enough to satisfy my curiosity, because it's just someone repeating information from another source without citing it. HOWEVER, because the screen name of the author of said source was mentioned, I looked for other forum posts by DV52 on the relevant forums. These threads that DV52 has posted in go into much more detail:

• SOC Battery | OBDeleven (June 2016)
• Start stop | OBDeleven (August 2016)
• Battery Charge option not available | OBDeleven (January 2018)
• Learning new battery for Golf Sportsvan | OBDeleven (February 2018)
• VCDS (VAG-COM) codes and programmable options for Golf Mk7 (vwwatercooled.com.au) (December 2019)
• Problem with start/stop system anyone? | Page 2 | GOLFMK7 - VW GTI MKVII Forum / VW Golf R Forum / VW Golf MKVII Forum (January 2020)
• 2019 RS3 Gateway Local Data Bus - Electrical Error | Page 2 | Ross-Tech Forums (March 2022)

It's interesting to see the understanding of the module evolve over the years. Essentially, the components that's being unplugged can be likened to one of those electrical clamp meters around the negative battery strap.

 

In summary, this is what I gleaned from the linked forum threads: unplugging the connector from the negative battery terminal means that there's no data for the battery history database and that the module is not able to supply the rest of the system with a reference for system voltage - different to battery voltage. I believe that the reason why the car continues to function normally is that anything that relies on knowing the system voltage gets by on measuring the battery voltage, like the alternator module CX1, as mentioned.

 

Don't take this as gospel, but I think the battery charging system has a set of known safe values that it will work with even if the battery history database and the system voltage level is not available. I think the only real consequence of disconnecting this plug is that your battery might not last as long. Until there's a better solution, I am happy with that trade-off. Auto start stop annoys me that much.

Thanks for providing more insight. Very helpful.