[cbarber]

Hi, I pulled the 7.5 amp fuse for the soundaktor (thanks for such clear instructions), and definitely appreciated the difference. I have a 2018 Boxster GTS. However, I found that having the fuse out drained my battery. I could go 24 hours between starts and it would be fine, but 36 to 48 hours, and the battery would be low enough to barely start, or not start the car.

It's been into the dealership twice, and today they said they ran a bunch of tests with and without the fuse, and found that with the fuse pulled, it draws more current than it does with the fuse in. Explanation is that with the fuse pulled, one of the computer systems keeps try to do something in some kind of loop (my best effort at paraphrasing).

I'd really like to get rid of this thing, but not at the expense of killing the battery.

I don't have the car hooked up to a maintainer yet (I don't have electricity where it's going to be parked for the next few months)

Very curious if anyone else can confirm this battery drain?

 

[cerbomark]

Interesting, I first pulled the fuse with no issue and then a few weeks later pulled the whole unit. Wonder if I shouldn't t put the fuse back now?
Go bak to page 13 and see my pics/post.

 

[Big Benny]

Strange to be sure ! I've had my fuse pulled for a couple of months, with no problems, as I'm sure many others have. I drive my car almost daily though. Once a month, I put it on
a smart charger, and it takes circa 5-6 hours at a 3A rate, to fully charge the battery ( this is with the car unlocked, and the cars systems active) . I have also discovered that with the headlights turned OFF, and monitoring the battery voltage, the volts don't seem to rise above about 12.4V for some time. If I leave the headlights on AUTO, I see the battery volts rise in about 15-20 seconds after a start to around 14.4V ( i.e the alternator is charging the battery ). My Audi RS3 also complained if the headlights were not left on AUTO, so the charging systems seems to like having the headlights selected to AUTO, maybe as a resonable load to trigger charging. I'd never noticed this before till watching either car.

These cars have multiple bus systems. On a CAN bus, all the modules on the bus are routinely checked for correct operation and being in an operable state. Pulling the fuse to the Soundactor may cause the BCU ( Body Control Module or whatever Porsche call it ) to keep pinging the Soundactor, but even then, the amount of power required to do this is not great. I've recently been involved with a light aircraft build that used a CAN Bus, and this is generally how they work..but a caveat here, Porsche may do things differently, and they have other bus in the vehicle that may work differently.

Others on here will no doubt be able to tell you if their cars sit longer between starts and if they have had any issues, but I don't remember reading of a similar problem.

From the only circuit diagram I have seen that was posted on here, the 7.5 Amp fuse was only powering the Soundactor. Pulling the fuse or physically unplugging the Soundactor ( a more fiddly time consuming job ) should have the same effect...the module will not be present on the CAN bus if I'm correct.

 

[cerbomark]

Ben, so if I pulled the whole unit should I put fuse back in?

 

[Big Benny]

Well, going on the only circuit diagram I have seen, pulling the Unit and then putting the fuse back would not make any difference to the system. I'm at a bit of a loss to understand the OP's problem, or what is causing it. We need others to tell us how long they have left their cars between drives, without a smart charger on the car, and with the fuse pulled.

A CAN Bus needs a termination resistor at each end of the bus, and in aircraft systems, sometimes that termination resistor can be located inside a bus Module, and removing the module physically can cause problems unless you place a temporary termination in place. But, if this was the case here, we would all be having problems ( well, those with the Soundactor physically removed ) but pulling the fuse leaves any termination in place if indeed the Soundactor is at one end of a CAN bus and provides an internal termination. I have no idea if this is the case, as Porsche play their cards very close to their chest regarding any systems info...it is almost impossible to get. I wrote to Porsche asking for any info they had on the design/systems in the 718 Cayman ( not service data ) and they told me " Nope...internal Company use only ".

As I posted above, I drive my car regularly, and place a smart charger on it once a month, the the charge time seems about right, so I won't notice the problem if it is being caused by having the fuse pulled. I'd also advise the OP to setup the info screen to let him see system voltage, and select headlights to AUTO, and see what the cars charging system is doing. It should indicate battery volts going up to over 14.4V approx to tell you the system is working properly.

 

[Big Benny]

Thinking a bit more about this, over a coffee, probably the best way to disable the Soundactor without risking upsetting anything in the Cars systems ( if this is indeed the case ), is to locate and measure the impedance of the actual transducer ( speaker ) and substitute a resistor of the same resistance. That way, fuse remains in, Soundactor electronics module remains plugged in to the bus and it pumps the racket it makes into a resistor that dissipates the output. I'm guessing that the Soundactor transducer is simply a speaker that has two wires going to it, from some sort of amplifier driven by the cars body control module that decides what we need to " hear ". Replacing the transducer with a resistor fools the whole system into thinking things are all good. I think the Boxster transducer was bolted to the front engine cover, and reasonably easy to get at, but I have no idea where the Cayman one is located.

Until I pulled my fuse, I thought my Bose stereo sounded crap, but once that Soundactor was disabled, it was a major improvement to the sound and the noise in the cabin, so iu have no desire to go back to enabling the thing.

 

[Treemagnet]

Pulled the fuse over 22 months ago. No issues when left unused (3+ weeks). Generally employ a CTEK MXS 5.0 when leaving unused for more than 2 or 3 weeks.

 

[Big Benny]

Thanks Treemagnet....that was what I thought would be the case, so what is going on with the OP's car is still a mystery. A few more on here confirming standing times like yours would confirm that pulling the fuse does not cause any problems. So,I wonder what is going on with just one car ? If the Dealer that he took his car to was right, you would assume more of us would be seeing starting problems .

 

[fontana302]

I can confirm that pulling the fuse will cause the following error on the CAN bus:

A bit of trickery to clear it by the way, not just re-inserting it.

 

[Big Benny]

Thanks fontana32 for that info...which does not surprise me. My adventures with the CAN bus on a Garmin flight system would do the same, bringing up a fault if any CAN module went off line or was disconnected, and advise on a page on the Pilots PFD Display . What to do next...does anyone have a lead as to where the Soundactor transducer lives inside a 2020 base Cayman ? If it is reasonably easy to get to, I'll replace the transducer with a resistive load and put my fuse back. I've got a iSoft ( ?? ) CAN bus reader, but have not used it since I pulled the fuse.

Do you have the procedure to reset the timeout fault ?

 

[Scrounger]

The speaker module lives behind the carpet behind the seats just above the armrest. Tbh I can’t see this being too much of an issue. I pulled my fuse on day 2 of ownership and haven’t had an issue yet (touch wood) although mine is a daily. I’ve bagged the fuse and stick it to the side of the fuse box stating what fuse it is and where it comes from. If it pulls a fault at service then the technician can reinstate it if he feels the need.

 

[JazzCatGab]

I pulled my fuse about 2 years ago and as a toy, my car isn't driven to a schedule. In good weather, it may go out on a weekly basis, though sometimes more. It has sat for a few weeks in a row without a charger. Like @Treemagnet I put it on the maintainer if I know it won't be used for 3 weeks or more. Never have seen any indication that the battery was having an issue.

 

[Big Benny]

I'll do a scan using my iCarsoft and see if I have an E-Sound timeout fault on the CAN bus. If I do, I'll put the 7.5A fuse back in and see if the fault clears. On the Garmin aircraft system, it will clear the fault after a successful " ping " from the reinstated module. This should happen after a power down/power up cycle, but may not be the saem for the cars CAN bus. I still cannot see the CAN system causing a battery to go down so quickly as the OP has experienced, but, more investigation needed. I'll go looking for the Soundactor transducer now that I have an idea where it lives.

 

[ArchiProf]

I disconnected the Soundaktor module before the fuse solution was posted here (see page one of this thread) and therefore have not removed the fuse. I wonder if this action causes the same fault as removing the fuse?

 

[MR69 ALB]

I have the full electrical schematics of the 981/982 platform, the soundakator and its fuse is a standalone circuit and supports nothing else, the code error is also a class c. Error that is recorded without any possible circumstance if left.
the amount of people who have removed the fuse must run into i the thousands and any problems would have been reported en mass on this site and others in inter web land if there were any repercussions For removing the fuse.
cheers A

 

[DriveInHouston]

In 2019 I've been on vacation to Greece for 7 weeks, the car was left unlocked and with the windows down in NYC. The fuse was pulled in early 2019. No issues!

 

[johan]

I dont think it matters, but there is two sound aktor systems.
The first has a tactile transducer and the control unit/amp sits in the rear trunk.

The newer has a normal speaker and i am pretty sure the control unit/amp sits just beside it

 

[MR69 ALB]

This should sort it out for everyone

The Can Bus system signals the actuator to work when the sport button is pressed there is a program that the actuator folllows depending what mode the gearbox is in gives a pre designated sound or drone in my case!!!
Cheers A

 

[Big Benny]

I disconnected the Soundaktor module before the fuse solution was posted here (see page one of this thread) and therefore have not removed the fuse. I wonder if this action causes the same fault as removing the fuse?

Removing the fuse depowers the module on the CAN bus...unplugging it at the module would have exactly the same effect, and it would not show up on a bus scan. What on going effect that has is the question.

 

[Big Benny]

I have the full electrical schematics of the 981/982 platform, the soundakator and its fuse is a standalone circuit and supports nothing else, the code error is also a class c. Error that is recorded without any possible circumstance if left.
the amount of people who have removed the fuse must run into i the thousands and any problems would have been reported en mass on this site and others in inter web land if there were any repercussions For removing the fuse.
cheers A

Thanks for the info. I'll use my iCarsoft device to see if I can see an error code ( my fuse has been pulled months ago ). I've noticed no on going issues since doing so, but any information about the cars systems is happily received, and I agree with your opinion...we would have seen lots of posts if there was any problems generated by pulling the fuse.
It's a shame that info about the cars systems is so hard to come by.