hello peeps,

i posted elsewhere a while ago re: fitting a sub in the boot from the standard head unit. I booked it in at a local car audio place and took it on saturday to have the sub fitted [carried forward from previous car]. Anyway, it was done as requested so i drove off and was quite happy with the result..however within 5 mins there was an error: flashing electric wire icon and the error "start/stop system error". this was intermittent at first, but now it's permanent. After some fiddling i discovered that system is deactivated due to this error and now doesn't switch the engine off at idle. The error immediately flashes up on starting the car.

 

So... now i need to go back to the car audio place, however i'm a bit dubious about letting them anywhere near it. I've unplugged the sub from the power etc to check if it was some kind of electrical drain problem, however this hasn't improved matters. I'm thinking they've damaged something while at the back of the head unit. My other option is to take it direct to skoda and just be honest about it and see what they say. That could run into lots of chin scratching, tutting and requests for money though.

 

Does anyone have any clue what might have happened other than physical damage? note my car is a 2014 octavia VRS

 

Thanks

Chris

Edited 11 May, 201511 yr by zombiefly

The 'audio' company will know for sure what they've messed with so they'd be my first port of call. It might only be something simple after all.

yeah. i did take it back immediately but the error cleared itself after stopping the car. they were closing up for the day so there was little i could do on saturday, at least they are aware of the issue though so i'll give them a ring this morning and see what they say.

... you are in a whole world of pain unless your car audio suppliers fix this.

 

They haven't wired anything directly to the battery have they to power the amp - that is a big no no on these cars due to the battery management systems.

Are you local to anyone with VCDS who can get a scan of the car prior to your audio guys touching it again - there will be a fault code logged which will give an indication as to why .....

... you are in a whole world of pain unless your car audio suppliers fix this.

 

They haven't wired anything directly to the battery have they to power the amp - that is a big no no on these cars due to the battery management systems.

 

yes they have. which i've concluded is the problem here.

 

here's my findings which i've sent to the audio company:

 

if i unplug the connector block on the sub [power/speakers/remote] start the car, wait 5 mins, stop the car, then start the car. the stop start system is working again. I've tested it for a good while stopping/starting and driving and the system is still working.

i plugged it all back in on the way back home last night and both the sub/start stop system worked for a time, then 5 mins in, the start stop system disabled again.

 

so i did some further research and discovered that the start stop system has a special type of battery and monitors the drain to ensure that it can rapidly start the car. i found many posts about aircon, heated windows etc causing the system to disable as the ECU considers the drain on the battery too high to ensure a rapid start. So, my basic conclusion here is that there is no problem with your fitting, it's the car deciding that the battery is not in the right state to allow the start stop to function.

 

 my conclusion is as you say, the direct amp wire to the battery is causing the problem as the monitoring systems are deciding that the battery state is not acceptable for start stop. So, i'm not a fan of start stop, so i think having it disabled is the way to go. providing the system doesn't perform background checks then it should stop the errors. When i take the car back at the end of my contract i'll remove the sub and have it switched back on...

 

thanks for the help guys, bring back the days of the 80's ford fiesta wiring!

Edited 12 May, 201511 yr by zombiefly

I was gonna say it will be something to do with the way it's wired to battery as my misses has a fiat 500 which on that forum some chap wired in a sub and amp and it was a nightmare with the stop start :-/ due to it tricking the battery into thinking it's draining/empty due to the current needed for the amp

I was gonna say it will be something to do with the way it's wired to battery as my misses has a fiat 500 which on that forum some chap wired in a sub and amp and it was a nightmare with the stop start :-/ due to it tricking the battery into thinking it's draining/empty due to the current needed for the amp

 

sounds like the same issue, did you get it fixed? i'm not sure there is another way of wiring the amp to the battery in this case.

Oh dear, sounds a bit of a mess, I'm not sure your fitters know their way around a modern car's electrics.  Hope they/you/someone gets it sorted swiftly.

 

Hows the sound now, and what did you do?  Just amp from the speaker line outputs from the bolero and that powering an additional sub, or powering door speakers/ new door speakers?

 

Hope the sound is now to your liking.

Nothing should be wired directly to the battery and bypass the battery monitoring module.

Sounds like a fire waiting to happen to me .......

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I'm so glad I've seen this thread, as I have an under seat sub from my previous car that I've been waiting to get round to fitting myself for a while now. I'd be interested to know if you can wire it up some other way to make it work properly though. I wonder if the guy with the £2k upgrade is having any issues too then?

Oh dear, sounds a bit of a mess, I'm not sure your fitters know their way around a modern car's electrics.  Hope they/you/someone gets it sorted swiftly.

 

Hows the sound now, and what did you do?  Just amp from the speaker line outputs from the bolero and that powering an additional sub, or powering door speakers/ new door speakers?

 

Hope the sound is now to your liking.

 

well i had fli 10 inch sub unit which i'd previously used in my previous vrs, which wasn't an issue as i'd replaced the head unit. Given the complexity of doing that in the new car, i simply wanted to jack the sub into the back of the head unit. i attempted this myself, but couldn't even work out how to remove the HU from the dash! so i took it to a local place to have them fit it. I bought all the parts and it cost me £80 for them to do it. basically they've run a remote cable from the power on the back of the HU and jacked the rear speaker wires which they've run into the boot into a low level converter plus a 12v feed [fused] direct from the battery.

 

Sound quality is as good as i was expecting, the stock system is seriously lacking in bass unless i crank the bass frequency up to 9, the sub is enhancing the missing frequencies, i've got it turned down quite low so it's just filling in the background. I'd say it sounds very good for a cheap solution and i'm definitely happy with the result, the downside is now i have this problem with the start stop system.

 

There is a 12v socket in the boot. the car audio place said this wasn't acceptable for powering the sub. I never take anyone's word for anything so tonight i'm going to attempt to power the sub from this and see what happens. the worst that will happen is i'll blow the fuse. with any luck it will work as expected AND be understood by the battery management thing, which might mean the start stop still works.

 

or i'll melt the wires and ruin the car... 

Edited 12 May, 201511 yr by zombiefly

I'm so glad I've seen this thread, as I have an under seat sub from my previous car that I've been waiting to get round to fitting myself for a while now. I'd be interested to know if you can wire it up some other way to make it work properly though. I wonder if the guy with the £2k upgrade is having any issues too then?

 

i just spoke to skoda as their canton system is an upgrade and involves an amp so i was wondering how they got around the problem i am having. I'd read that it was possible to adjust the tolerance on the battery management [temp/voltage] so i asked about that. the "master technician" at my local dealer said that this was an unsupported modification and would not discuss it with me! I asked if they could switch off the start stop function as i didn't want it, the answer was no to that too. the only thing he did answer with was "if you power anything from the battery, it will always see that as a problem and disable start stop due to the safety circuit" so as far as i can tell, it isn't possible to install after market audio equipment to cars with start stop without the battery management freaking out.

 

this is all news to me. i've ALWAYS replaced stock entertainment, now it seems i'm unable to do this without paying a fortune for some after market dealer approved solution. It's made worse this time round as i'm on my first PCP with this car, so i definitely can 't use one of my insulation tape/connector block botch solutions this time round!

 

I would be really interested in hearing from someone who's managed to add additional battery feeds to a car with start/stop

Edited 12 May, 201511 yr by zombiefly

I guess if he already had canton, he's used the power going to the canton sub for his setup then. I kinda doubt you'll be able to use the 12v socket somehow, far too much current being drawn!

Nothing should be wired directly to the battery and bypass the battery monitoring module.

Sounds like a fire waiting to happen to me .......

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it's fused so there should be no risk of fire. what do you mean bypassing? is there an option for wiring something from the other side of the monitor, like as an accessory?

My sub has been wired (directly) from the Battery as well, but I'm having no issues at all. In my case though, the car audio supplier was chosen by my Skoda dealer (they have a partnership) and they have enough know-how of Skoda cars to setup such a thing up. I would suggest your car audio supplier takes it up with Skoda to receive info as to how to manage these installations on new(er) Skoda's. 

 

The way I see it, they did something to you car even though you trusted them with the installation. Let them solve it, not your problem.

Edited 12 May, 201511 yr by Diango

Take the power from the fuse box.

 

BTW, the 'head unit' in the dash is just a dumb screen.  The head unit is actually in the glove box.

Edited 12 May, 201511 yr by neiln

As has been said, you cannot run the amp directly from the battery, it needs to be connected on the other side of the battery management module. You'll get loads of faults with it wired directly to the battery and could indeed end up damaging the battery management module.

 

The faults occur because the car can see the battery drain but has no idea what is causing it, so it tries to shutdown systems to compensate. It will keep shutting down systems until it finds what is causing the unexpected drain, which because your wired directly to the battery it never will. First to go will be stop start, then keyless entry and other convenience functions will all be disabled one by one.

 

Your amp needs to be wired into a circuit monitored by the module, then it can see the battery drain so knows where its coming from and how much it is and most likely retain all systems as functional.

 

My Audi has the same system, and right by the battery are big notices and warnings about wiring directly to the battery. The positive terminal has a big cap on it, with a big red X on it.

Alternatively and I'll put it far simplier, remove the black wire powering the amp from the battery and connect it to upper of the two earth lugs directly behind the battery.

 

This should remove the problems you're encountering.

 

Regards

T

Alternatively and I'll put it far simplier, remove the black wire powering the amp from the battery and connect it to upper of the two earth lugs directly behind the battery.

 

This should remove the problems you're encountering.

 

Regards

T

 

 

Take the power from the fuse box.

 

BTW, the 'head unit' in the dash is just a dumb screen.  The head unit is actually in the glove box.

 

 

As has been said, you cannot run the amp directly from the battery, it needs to be connected on the other side of the battery management module. You'll get loads of faults with it wired directly to the battery and could indeed end up damaging the battery management module.

 

The faults occur because the car can see the battery drain but has no idea what is causing it, so it tries to shutdown systems to compensate. It will keep shutting down systems until it finds what is causing the unexpected drain, which because your wired directly to the battery it never will. First to go will be stop start, then keyless entry and other convenience functions will all be disabled one by one.

 

Your amp needs to be wired into a circuit monitored by the module, then it can see the battery drain so knows where its coming from and how much it is and most likely retain all systems as functional.

 

My Audi has the same system, and right by the battery are big notices and warnings about wiring directly to the battery. The positive terminal has a big cap on it, with a big red X on it.

 

 

Alternatively and I'll put it far simplier, remove the black wire powering the amp from the battery and connect it to upper of the two earth lugs directly behind the battery.

 

This should remove the problems you're encountering.

 

Regards

T

 

this is great stuff, thanks guys

 

I've spoken to the audio fitter and it's booked in on friday for them to wire it from the fuse box. If this is done, does the earth still need to be moved to these lugs behind the battery?

The O3's have a neutral earth therefore, if they wire through the fuse board it won't be required as its already done by the fuse board, mines just a little get-around to save working cables through the car and its so close and easy to do, for anything powered under the bonnet its a no-brainer.

 

But no, I wouldn't like to say what aftermarket equipement you could possible have under bonnet that would need power.

 

Glad your people are doing the right thing and putting right their mistake, must have been the trainee.

I looked into this for my MK7 Golf before I ordered it & decided that the cars electrics were too much of a hassle with the security protocols, HU info on car lost etc etc  if going down the aftermarket road like I had done in previous cars...............So I ticked the Dynaudio box & saved myself the trouble/problems.

 

I have started a thread on coding the CAN-Gateway module for replacing batteries here

 

http://www.briskoda.net/forums/topic/353688-replacing-main-car-battery-might-require-can-gateway-coding/

 

& of particular interest is my post number 21 here

 

http://www.briskoda.net/forums/topic/353688-replacing-main-car-battery-might-require-can-gateway-coding/?p=4236598

 

which has pics from VCDS of some of the battery magement functions in the CAN-Gateway module, all from my MK7 Golf which uses the same modules as your MK3 Octavia

If you wire up to the points provided in the fuse box in the engine bay it will be fine, as others have said.

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well more testing has left me even more confused.

 

1. i disconnected the direct battery feed to the sub/amp. Fuse removed, no more connection.

2. start/stop working again

3. i plugged the sub/amp power into the 12v accessory feed in the boot to see what happened. started car, sub powers on. everything seems to work

 

then while driving, start/stop is disabled again. 

 

so... if i get a problem when using the already fused and understood (battery management) 12v accessory feed in the boot, is this going to be the same if i run a direct power feed from the fuse box? how can it be any different? i was planning on using one of the accessory fuses for this purpose, which is essentially what i'm doing now.

 

this is a nightmare. 

Edited 13 May, 201511 yr by zombiefly

What reason was given for SS being disabled? Did it day Start Stop System Error, or was it one of the informational messages such as Engine must be running

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