Model 3 SR / SR+ owners:
Newer 2020+ model 3 SR+ >>> Your car might not come with rear shelf speakers so you need to add in the speakers..See jpsingh user guide and removal of the rear shelf.
I completed an upgrade to my SR+ sound system. Following from posts before and thanks to users @fstr, @_Travis_ , @Dfwatt, @Flashflooder, @LRonHoyabembe, @Ingineerix and many others in here I was able to do it myself.
Moderator: Please don't merge this thread. I like to create this How-To thread specific for SR / SR+ car build that has different wiring from the premium build, and a specific thread like this for SR for easy visibility and SR to share thoughts and not get confused with the premium build mix.
SR+ speaker system background notes: It is not possible (based on my car setup) for future software updates to activate the side mirror tweeters and rear shelf speakers. I confirmed in my installation that those speakers are there but the wiring for the speakers did not connect to anything. Also no subwoofer.
Plan: Tap and get signals from the left-right door woofer to use for the signal of the aftermarket subwoofer. Also, tap and get signals from the rear door speakers 4" to get signal for the two-door tweeters and two rear shelf speakers. I have never done a sound upgrade for a car before but my dislike for the SR+ sound compelled me to do the upgrade myself (I also didn't trust outside car stereo shops).
Basically, after done, it will power the two tweeters near the door windows and power two rear 4" speakers in the back of the car, and also add a subwoofer that will fit in the lower area of the trunk.
The four main products I'm using are: Pioneer 10" shallow subwoofer, Alpine KTP-445U amp (to power the extra speakers that are inactive now), LC7i, and Pioneer GMD8701 amp
I could have combined the two amps and picked maybe a 5 channels amp instead of two amp but already brought it.
----Update on subwoofer: I find the 12" sealed pioneer to be overpowered for my music listening (nonrap/hip hop genre). Consider a smaller sealed sub if you're into vocal/classical music. So far, I'm using 10" and I like it, but maybe even 8" sealed pioneer can be good too. I had to face my sub facing up because it caused too much distortion when facing down in the sub-trunk area. So if your sub sounds terrible with a lot of rumbling/distortion, try placing it in different directions.
Direction:
Please look at this post to find the installation guide: first post. I'm adding more information below to explain more.
WIRING/POLARITY: Since I couldn't open up the rear shelf to access the speakers' polarity, I brought a polarity tester device. This will save you a lot time so you don't have to open up the doors to find speaker coloring/polarity.
Rear shelf 4" speakers: (Right: Yellow - , Gray +) (Left: White- , Purple +)
Rear door 4" speakers: (driver's (left) Black -, Red +) (Passenger (right) Blue +, Green -)
Door mirror tweeters: (Passenger (right): Red - , White +) (driver's (left): Purple - , Black +)
-Caution: remember to turn on your amp high pass filter/add bass blocker when powering tweeters connections
Door woofer: (driver's (left): Blue -, White +) (Passenger (right): Orange +, Black -)
Time-saving step: For tapping signal from the L/R rear door 4" speakers, I originally had to open up the B pillars (as shown in the picture below) because I had no idea what coloring they were. But now knowing what color they are, and knowing that these wires had to run to the front of the car, YOU can tap these wires for a signal without the hassle of opening up the B pillars. Wires will be taped and twisted around each other, and are quite thin.
The tricky part: making a connection to wire the right door tweeter. You will know what I mean when you attempt it. In my SR+ build in March, the left side has extra wiring coming out of the white plastic connector, whereas the right tweeter has no wiring after the white connector. The space on the right was tight that I ended up splicing the wire out of the white connector since there was no space inside to use a t-tap (I use a wire stripper in there, strip it out using an 18/20g strip, and connect a new wire to it). Also, remember the left driver door mirror tweeter has extra wires coming out after the white connector, you need to cut these existing wires out otherwise you will do some sort of back feeding to the stock amp (so not-tap at all for this driver side tweeter, only straight connection to this tweeter and amp).
---Update: @Vector used a PC socket adapter on this passenger tweeter, so this method might be easier for you, read here
Removal of door trim: to access the wiring for the rear door speakers, you need to remove the bottom B panel trim. You need to remove the front and back of the trim before you can remove the middle B panel trim. The removal should be sequential like this: remove the bottom rear seats and side door leather, remove the bottom black plastic trim (just pull up), remove black trim near the driver seat, and finally remove B pillar black trim by pulling away starting from the bottom. I just opened the B panel trim just enough to access wires for the signal. Caution: there's a wire loom that sits on the door trim near the front, don't try to splice any of this since it has an orange sticker that says attempting to do so might trigger the airbag. Check out this schematic of door trims.
T-tap: The wire gauge for the tweeters and 4" speakers are thin (maybe 20gauge), so the t-tap might or might not work. I t-tap several wires but when checking, one connection plastic covering didn't sheer off the t-tap for there to be a connection. I ended up splicing the wires for these to make sure the connection works. You might or might not experience this. If you don't want to slice wires, you can also try the posi-tap connector which is more expensive. I don't recommend the regular t-tap connector.
Penthouse 12V+ to power amp: A trick I found if you are afraid of shorting the connector when working, you can wait till the penthouse 12v+ is off. Leave all doors & trunks open for some amount of time, after a while, you will hear a big clunk near the penthouse to indicate the high voltage connector is off. You can check that this 12V penthouse is off by trying to adjust the front seats (it won't move), the screen is off, and the trunk lighting is off. I tested using a multimeter on the penthouse 12V at this time and it registered no power. I use the same bolt on the 12V+ by taking the lid off the red plastic covering and removing the bolt and putting the connection under it and screwing it back again.
12V+ Remote in As noted by user first, the 12V+ (aka VCLeft 12v) to supply the amp remote in that Ingineerix video pointed to has a thick red wire attached to it in my car. I believe the newer car build might have a red wire attached to this pin. So all you need to do is t-tap into this for power. For my setup (yours can vary), this accessory LCleft 12V+ power the LC7i "12V power", then LC7i "remote out" line powers the alpine "remote in", then the alpine "remote out" powers the subwoofer amp "remote in". My LC7i "remote in" is empty since I have the LC7i jumper setting for GTO on (see pic).
Alpine KTP amp: If you have trouble figuring out which wiring configuration works best you can try this. I have the rear doors speakers splits to 4channel(=8wires) > go to LC7i main+ch1 input>LC7i output main+ch1 go to alpine input for front+rear. Set the alpine jumper to 4ch and speaker input(non-RCA).
LC7i: If you use LC7i leave GTO on as default (see pic). Also, this LC7i has AccuBASS which is very useful to increase the low-end frequencies that are needed for the subwoofer.
Grounding terminal: SR+ has a black plastic covering where the subwoofer would be in a premium. I use the bolt that holds this plastic piece near the right taillight as my ground (-) wiring.
Amplifier: The Pioneer GMD8701 is a refreshed 2019 lineup for pioneer amps and it comes with a nice wire remote control for bass. I read certain high power amps might cause the error "cannot maintain vehicle power" but this one so far has not given me any error. If you want to be sure or if u use a big amp, you can add a relay from this thread. I didn't do relay and it has been 3 months with this setup and the car hasn't thrown any system error.
Sub Trunk Guide: You can run all the wires to the right side below the trunk liner (see video below for trunk removal), and from there use a small knife to cut a cross-cut (+) in the sub trunk for all wires to pass into. I do this cut instead of drilling since later on if the wires are removed, the sub-trunk fabric falls back into place as if it wasn't cut out before. In this setup, all amp, lc7i, and subwoofers are hidden in the sub-trunk area. Caution: to prevent the liquid bottom from dripping into this area and ruining the equipment, be sure you have an all-weather rubber mat on the top or place something in this sub-trunk area to prevent accidental liquid from going in.
Helpful videos:
Ingineerix 12V+ accessory video , front door plastic trim removal, rear door removal, trunk removal lining, and backseat removal
Materials used: 100ft speaker wires, t-tap connector or positap, 8 gauge subwoofer wiring kit or 4 gauge kit
Future work for SR+ sound: The top speakers near the A-pillar aren't working now. I might attempt to run wires down and power the speakers in parallel to the door mirror tweeters.
--Update on this top A-pillar speakers: I was able to do this by splitting the power going to the mirror tweeters. You can read it here. I would say this adds a slight moderate sound improvement. Read here
That's all for now. Please share your thoughts, set up, and equipment used.
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Newer 2020+ model 3 SR+ >>> Your car might not come with rear shelf speakers so you need to add in the speakers..See jpsingh user guide and removal of the rear shelf.
I completed an upgrade to my SR+ sound system. Following from posts before and thanks to users @fstr, @_Travis_ , @Dfwatt, @Flashflooder, @LRonHoyabembe, @Ingineerix and many others in here I was able to do it myself.
Moderator: Please don't merge this thread. I like to create this How-To thread specific for SR / SR+ car build that has different wiring from the premium build, and a specific thread like this for SR for easy visibility and SR to share thoughts and not get confused with the premium build mix.
SR+ speaker system background notes: It is not possible (based on my car setup) for future software updates to activate the side mirror tweeters and rear shelf speakers. I confirmed in my installation that those speakers are there but the wiring for the speakers did not connect to anything. Also no subwoofer.
Plan: Tap and get signals from the left-right door woofer to use for the signal of the aftermarket subwoofer. Also, tap and get signals from the rear door speakers 4" to get signal for the two-door tweeters and two rear shelf speakers. I have never done a sound upgrade for a car before but my dislike for the SR+ sound compelled me to do the upgrade myself (I also didn't trust outside car stereo shops).
Basically, after done, it will power the two tweeters near the door windows and power two rear 4" speakers in the back of the car, and also add a subwoofer that will fit in the lower area of the trunk.
The four main products I'm using are: Pioneer 10" shallow subwoofer, Alpine KTP-445U amp (to power the extra speakers that are inactive now), LC7i, and Pioneer GMD8701 amp
I could have combined the two amps and picked maybe a 5 channels amp instead of two amp but already brought it.
----Update on subwoofer: I find the 12" sealed pioneer to be overpowered for my music listening (nonrap/hip hop genre). Consider a smaller sealed sub if you're into vocal/classical music. So far, I'm using 10" and I like it, but maybe even 8" sealed pioneer can be good too. I had to face my sub facing up because it caused too much distortion when facing down in the sub-trunk area. So if your sub sounds terrible with a lot of rumbling/distortion, try placing it in different directions.
Direction:
Please look at this post to find the installation guide: first post. I'm adding more information below to explain more.
WIRING/POLARITY: Since I couldn't open up the rear shelf to access the speakers' polarity, I brought a polarity tester device. This will save you a lot time so you don't have to open up the doors to find speaker coloring/polarity.
Rear shelf 4" speakers: (Right: Yellow - , Gray +) (Left: White- , Purple +)
Rear door 4" speakers: (driver's (left) Black -, Red +) (Passenger (right) Blue +, Green -)
Door mirror tweeters: (Passenger (right): Red - , White +) (driver's (left): Purple - , Black +)
-Caution: remember to turn on your amp high pass filter/add bass blocker when powering tweeters connections
Door woofer: (driver's (left): Blue -, White +) (Passenger (right): Orange +, Black -)
Time-saving step: For tapping signal from the L/R rear door 4" speakers, I originally had to open up the B pillars (as shown in the picture below) because I had no idea what coloring they were. But now knowing what color they are, and knowing that these wires had to run to the front of the car, YOU can tap these wires for a signal without the hassle of opening up the B pillars. Wires will be taped and twisted around each other, and are quite thin.
The tricky part: making a connection to wire the right door tweeter. You will know what I mean when you attempt it. In my SR+ build in March, the left side has extra wiring coming out of the white plastic connector, whereas the right tweeter has no wiring after the white connector. The space on the right was tight that I ended up splicing the wire out of the white connector since there was no space inside to use a t-tap (I use a wire stripper in there, strip it out using an 18/20g strip, and connect a new wire to it). Also, remember the left driver door mirror tweeter has extra wires coming out after the white connector, you need to cut these existing wires out otherwise you will do some sort of back feeding to the stock amp (so not-tap at all for this driver side tweeter, only straight connection to this tweeter and amp).
---Update: @Vector used a PC socket adapter on this passenger tweeter, so this method might be easier for you, read here
Removal of door trim: to access the wiring for the rear door speakers, you need to remove the bottom B panel trim. You need to remove the front and back of the trim before you can remove the middle B panel trim. The removal should be sequential like this: remove the bottom rear seats and side door leather, remove the bottom black plastic trim (just pull up), remove black trim near the driver seat, and finally remove B pillar black trim by pulling away starting from the bottom. I just opened the B panel trim just enough to access wires for the signal. Caution: there's a wire loom that sits on the door trim near the front, don't try to splice any of this since it has an orange sticker that says attempting to do so might trigger the airbag. Check out this schematic of door trims.
T-tap: The wire gauge for the tweeters and 4" speakers are thin (maybe 20gauge), so the t-tap might or might not work. I t-tap several wires but when checking, one connection plastic covering didn't sheer off the t-tap for there to be a connection. I ended up splicing the wires for these to make sure the connection works. You might or might not experience this. If you don't want to slice wires, you can also try the posi-tap connector which is more expensive. I don't recommend the regular t-tap connector.
Penthouse 12V+ to power amp: A trick I found if you are afraid of shorting the connector when working, you can wait till the penthouse 12v+ is off. Leave all doors & trunks open for some amount of time, after a while, you will hear a big clunk near the penthouse to indicate the high voltage connector is off. You can check that this 12V penthouse is off by trying to adjust the front seats (it won't move), the screen is off, and the trunk lighting is off. I tested using a multimeter on the penthouse 12V at this time and it registered no power. I use the same bolt on the 12V+ by taking the lid off the red plastic covering and removing the bolt and putting the connection under it and screwing it back again.
12V+ Remote in As noted by user first, the 12V+ (aka VCLeft 12v) to supply the amp remote in that Ingineerix video pointed to has a thick red wire attached to it in my car. I believe the newer car build might have a red wire attached to this pin. So all you need to do is t-tap into this for power. For my setup (yours can vary), this accessory LCleft 12V+ power the LC7i "12V power", then LC7i "remote out" line powers the alpine "remote in", then the alpine "remote out" powers the subwoofer amp "remote in". My LC7i "remote in" is empty since I have the LC7i jumper setting for GTO on (see pic).
Alpine KTP amp: If you have trouble figuring out which wiring configuration works best you can try this. I have the rear doors speakers splits to 4channel(=8wires) > go to LC7i main+ch1 input>LC7i output main+ch1 go to alpine input for front+rear. Set the alpine jumper to 4ch and speaker input(non-RCA).
LC7i: If you use LC7i leave GTO on as default (see pic). Also, this LC7i has AccuBASS which is very useful to increase the low-end frequencies that are needed for the subwoofer.
Grounding terminal: SR+ has a black plastic covering where the subwoofer would be in a premium. I use the bolt that holds this plastic piece near the right taillight as my ground (-) wiring.
Amplifier: The Pioneer GMD8701 is a refreshed 2019 lineup for pioneer amps and it comes with a nice wire remote control for bass. I read certain high power amps might cause the error "cannot maintain vehicle power" but this one so far has not given me any error. If you want to be sure or if u use a big amp, you can add a relay from this thread. I didn't do relay and it has been 3 months with this setup and the car hasn't thrown any system error.
Sub Trunk Guide: You can run all the wires to the right side below the trunk liner (see video below for trunk removal), and from there use a small knife to cut a cross-cut (+) in the sub trunk for all wires to pass into. I do this cut instead of drilling since later on if the wires are removed, the sub-trunk fabric falls back into place as if it wasn't cut out before. In this setup, all amp, lc7i, and subwoofers are hidden in the sub-trunk area. Caution: to prevent the liquid bottom from dripping into this area and ruining the equipment, be sure you have an all-weather rubber mat on the top or place something in this sub-trunk area to prevent accidental liquid from going in.
Helpful videos:
Ingineerix 12V+ accessory video , front door plastic trim removal, rear door removal, trunk removal lining, and backseat removal
Materials used: 100ft speaker wires, t-tap connector or positap, 8 gauge subwoofer wiring kit or 4 gauge kit
Future work for SR+ sound: The top speakers near the A-pillar aren't working now. I might attempt to run wires down and power the speakers in parallel to the door mirror tweeters.
--Update on this top A-pillar speakers: I was able to do this by splitting the power going to the mirror tweeters. You can read it here. I would say this adds a slight moderate sound improvement. Read here
That's all for now. Please share your thoughts, set up, and equipment used.
