Hi!
I havent’ been here for a while.
I’m glad that some of You went the way to improve DS4 stock audio to something better using Focal and other components.
I’d like to ask anyone if You have a pinout of voicecoils for the factory Focal subwoofer?
It’s powered by three separate channels from the amplifier.
I have DS4/Peugeot 308/408 subwoofer - they are identical 3-coil subwoofers - and I need to know how three coils of the subwoofer are split on the yellow connector.
I’ve found some pictures of the speaker inside, it has 6 wires (three “+” and three “-”) but there is no description which is which.
It looks like full colors are “+” and the ones with white stripes are “-” but I’m not sure.
Service box is no longer available so… 
Regards!
It’s almost as you described, with the yellow wire being ground and the yellow wire with the stripe being the coil’s power supply (red, blue same). You can always reverse the polarity to change the phase by 180 degrees, as the effect might be better. You’ll definitely hear it.
You can also test coil with a single AAA battery. If the diaphragm moves forward, the positive of the coil is where the positive of the AAA battery is. If moves backward, the positive of the battery is where the negative of the coil is.
Something is odd in the connection of subwoofer.
I have pulled the speaker from the subwoofer box and it looks like this.
Right side are all colors with white stripes and left side is all full colors.
I don’t quite undestand why blue and red wires are placed in such odd way which would suggest bridged connection in the amplifier.
To switch polarity of all the coils I have to do it on the socket (I’ve already ordered proper connectors to do it), because cables in the subwoofer BOX are too short to simply swap them - the right side is too short to make it to the left of the subwoofer speaker.
I will make an adapter but before swapping, check each coil impendance just to be sure, maybe they are all 1 Ohm which will give 3 Ohms total impendance in serial connection.
If You look closely You will notice that terminals for the cables have 3 sizes so You can swap polarities but cannot swap channels - connectors won’t fit.
It may be the case that the subwoofer is wired improperly from factory (180o out of phase) since that is possible and that’s what I’m trying to reverse.
I have typical out of phase situation in my opinion, setting the audio focus to ALL gives much more bass upfront than settings to FRONT Optimized which kills bass in the front.
Actually in FRONT Optimized setting if I set subwoofer to -4, there is more bass than on “0” setting.
Maybe electrical schematic would provide some more data but I doubt it.
Test each coil with an AAA battery. It’s safe. This will tell you everything and let you know if they’ve reversed the phase for some coil.
If it isn’t to much work, I can open up my subwoofer for reference.
In my car the bass is more present when choosing “front” compared to “all”. Sub + on EQ gives more bass then -, as it should be.
Wonder if it wouldn’t be easier to use @Andrew_PL suggestion, the issue might as well be with the door speakers, if the front speakers is out of phase.
If you can get to the amp, disconnect the socket and test speaker by speaker (with a friend and a flashlight) to see which way everything is moving?
To check the amplifier I would have to disassemble the right part of the trunk and I don’t want to do that right now.
I don’t think it’s problem with front door speakers because it would blend like shit with tweeters and center speaker - reversed polarity would be trough whole frequency range of midwoofer so from around 60Hz to somewhere around 2.5k.
Second thing is that between FRONT setting and ALL settings there is 100% reversed polarity on DSP processor itself because You can hear “pop” sound from subwoofer when switching from FRONT to INDIVIDUAL which is very distinctive for reversed polarity while playing music – interference from reversed sinewaves.
You don’t hear it when switching from FRONT to ALL and reverse because there is soft volume increase from mute to desired volume level which prevents “pop” from appearing.
They didn’t implement that soft volume up on switching from FRONT to INDIVIDUAL so the “pop” appears and there is no “pop” sound when switching from ALL to INDIVIDUAL because on ALL settings there is no polarity reverse on DSP processor for subwoofer.
I’ve made few car audios in my previous cars so I know these very distinctive events – I’m noticing this immediately.
Currently the issue that I have is in my Peugeot 408 with Focal sound system but sound system is exactly the same as in 308/DS4 (except C pillar speakers)/Citroën/Opel cars etc.
In my opinion the issue is caused by one of two reasons
- The system is 1:1 transferred from 308 which is a bit different car with completely different trunk (SW/Hatchback) so the wavelength is in different phase (180o or 90o difference) at listening position
- The subwoofer is badly connected (reversed) which is at first glance hard to do because wires with white stripes are shorter so they probably can’t be connected in a reverse way – I wasn’t able to pull them so that they would be long enough to connected them in opposite way
- Time alignment is fu**ed which would give exactly this effect
For now I suppose that left side of the speaker (according to the photo) is “+” terminal and right side is “-“ terminal.
In case of yellow cables that makes sense.
In case of red and blue cables, interesting thing is that they are not aligned like those yellow cables but You cannot switch them because the connectors are different – there are 3 sizes of connectors.
Assuming that they are properly made, You can only switch polarity for the whole speaker – all the coils but You cannot mix it in any different way – the connectors won’t fit.
Red cable and red with white stripes have the smallest connector.
Yellow cable and yellow with white stripes have medium sized connector.
Blue cable and blue with white stripes have the biggest connector.
I cannot switch those cables directly in the subwoofer because the right side cable (with “-“ polarity) is too short and I won’t reach the left side of the speaker in my case.
I will probably check the subwoofer with AAA battery to see if coils have polarization like I suppose it has.
Also bridged mode in factory amplifier doesn’t really convince me since with bridged channels You only use two wires, one is going to the “+” terminal of channel 1 and second is going to the “-“ terminal od channel 2 so there would be too much wires but without electrical schemas we really don’t know how they made that.
For DS4:
IVI HiFi Focal wires.pdf (169,1 KB)
IVI HiFi Focal.pdf (204,7 KB)
Thanks, from the schematics I see by PIN numbers on the socket that indeed those with white stripes - PIN number 1, 3 and 5 is negative and 2, 4 and 6 is positive and that corresponds to PIN numbers in amplifier so it’s using 3 separate channels to drive the SUB to increase output power to around 150W MAX RMS (~50W RMS per channel for a 12-way amplifier).
It’s clear when comparing to other speakers when there is a corelation between PIN numbers on the speaker and amplifier and it has to be “+”/”-“ terminal.
One thing that I have to check before proceeding to reverse the polarity (without the risk od damaging the speaker) is how coils are placed and their terminals installed on the speaker itself, maybe their “+” and “-“ terminals aren’t evenly placed left to right but distributed in more crazy way that’s why it looks odd on the speaker itself (crossed in “X” shape between red and blue cables)
Ps. 16 channel class D amplifier in DS is bullshit, 4 channels are driven directly from IVI (tweeters if I remember correctly) and the rest is driven from the Amplifier. Of course IVI can easily handle tweeters with very low power demands but there is a small lie in the adverts 
It’s easy to check. And what you’re writing is just aesthetics. It’s supposed to work and that’s it, but only a few people know how crazy it looks.
Ok so I have tested the subwoofer and PIN 1/2 3/4 5/6 are each individual coil with 2.5Ohm impedance each.
Testing with 1.5V battery confirmed proper subwoofer wiring at proper polarity the sub goes UP on each coil.
I have reversed the polarity by making an adapter with original plug and socket that reversed polarity at each coil.
Everything is now as it should be from the beginning.
There is so much bass upfront at FRONT optimized settings in IVI that I have LOW and SUB set to “0”.
Clearly DSP settings weren’t properly checked which in this price range of a car is unacceptable.
Thanks for support 
Changing the sub phase by 180 degrees often makes a much better impression.
Enjoy the sound.