[lorsben]

I recently picked up my 2023 EUV LT -- it does not have Bose sound system and I would like to do a full upgrade of the audio components. Since replacing the head unit is out of the question, I'm planning to tap into the speaker wires and run speaker wire input to a new amp (that accepts speaker wire signal as input) that I will put in the trunk. Then obviously I'll need to run speaker wire back from the amp to the upgraded speakers in the doors.

I took the door panel and trim off today, which was fairly straightforward. However, getting wiring through the door panel seems to be a challenge. I searched the forums and see lots of people who have tapped off the Bose system already in the trunk or simply replaced the factory speakers (using factory wiring). But has anyone successfully run wiring through the door? I'll attach a picture of the rear driver's side door that shows where the wiring would need to go through.

Another alternative I'm considering is just figuring out the wiring before it goes into the door panels -- splicing off the speaker wire before it goes into the door panel and utilizing the factory wiring through the door. This is probably what I'll do if getting wiring through the door panel is a major pain, as I really don't want to mess with the rubber grommets and risk allowing water/dirt in.

Any input would be appreciated!

 

[Electric Personality]

There has to be a to plug and play kit to wire an amp, no need to run new wires to the doors.

 

[LoneR]

Those rubber plug assemblies are not easy to mod. I would suggest cutting-in behind the b-pillar cover, where you're at in the pic. Those plug assemblies can be modded, but you run the risk of destroying the it. If you want to try it, remove the rubber cover by pulling the edges parallel to the body, at the pillar. The edges are tucked under the plug. Be careful not to damage the rubber cover. Once it's pull away, you can inspect the plug assembly for how it detaches from the pillar. The other side of the plug stays on the pillar but can be removed to the inside of the pillar, as it is part of the interior harness. Then you're left with a hole in the pillar. The side of the plug hanging from the door can be pushed back through the door frame. You have to squeeze the cover at the door frame. Make it pop through. The hole should be large enough for the plug, as well. It just a one piece harness assembly for the whole door electrical. Then you're left with a hole in the door frame. It's just a rubber, protective cover for the wires to the plug. When you're ready to put it back together, pull the pillar plug out through the pillar hole, reattach the plugs together, pull the rubber seal around the backside of the pillar plug and reinsert the assembly back into the pillar. It will snap into place and seal against the body. I hope that all makes sense to you without having to disassemble it for clarity. If you're careful and pay attention, it can be modded properly.

Addition: Sometimes the plug disconnects from inside the pillar first. The you release the outside plug and seal from the pillar, from the inside of the pillar as well. In this case, to reattach, you insert the outside portion of the plug into the pillar and snap into place. You have to press really hard sometimes. Then insert the inside portion of the plug.

 

[usedBolt]

You do want to be REALLY REALLY CAREFUL when messing with the B pillar in modern cars. A sensor for the side airbags is usually in there somewhere. The seat belts, also, are explosive pretensioner types that you need to deal with gently. It's worth buying the service manual ($400 for the 2017 Bolt from Helm; not sure about other years) and studying up on the deactivation/reactivation procedures. It might be more than just disconnecting the 12V battery.

 

[sir3lit]

I recently picked up my 2023 EUV LT -- it does not have Bose sound system and I would like to do a full upgrade of the audio components. Since replacing the head unit is out of the question, I'm planning to tap into the speaker wires and run speaker wire input to a new amp (that accepts speaker wire signal as input) that I will put in the trunk. Then obviously I'll need to run speaker wire back from the amp to the upgraded speakers in the doors.

I would suggest splicing in at the back of the radio...

Pin​	Size​	Color​	Circuit​	Function​	Terminal Type ID​	Option​
1​	0.75​	GN​	199​	Left Rear Speaker [+] Control​	II​	UQ3​
2​	0.75​	BU​	201​	Left Front Speaker 1 [+] Control​	II​	UQ3​
3​	0.75​	YE / BK​	117​	Right Front Speaker [-] Control​	II II​	UQ3​
4​	0.35​	BU / BK​	115​	Right Rear Speaker [-] Control​	III​	UQ3​
5​	0.75​	BN / BU​	118​	Left Front Speaker [-] Control​	II​	UQ3​
6​	0.75​	YE​	200​	Right Front Speaker 1 [+] Control​	II​	UQ3​
7​	—​	—​	—​	Not Occupied​	—​	—​
8​	0.75​	WH​	46​	Right Rear Speaker [+] Control​	II​	UQ3​
9​	0.35 0.35​	BU / GN BU / GN​	1304 1304​	High Speed GMLAN Serial Data [+] 9 High Speed GMLAN Serial Data [+] 9​	I I​	UKL - UKL​
10​	0.35 0.35​	WH / GN WH / GN​	1305 1305​	High Speed GMLAN Serial Data [-] 9 High Speed GMLAN Serial Data [-] 9​	I I​	UKL - UKL​
11​	0.35 0.35​	BU / GN BU / GN​	1304 1304​	High Speed GMLAN Serial Data [+] 9 High Speed GMLAN Serial Data [+] 9​	I I​	UE1/ UER - UE1- UER​
12​	0.35 0.35​	WH / GN WH / GN​	1305 1305​	High Speed GMLAN Serial Data [-] 9 High Speed GMLAN Serial Data [-] 9​	I I​	UE1/ UER - UE1- UER​
13​	0.35​	GN / WH​	24​	Backup Lamp Control​	I​	—​
14​	—​	—​	—​	Not Occupied​	—​	—​
15​	—​	—​	—​	Not Occupied​	—​	—​
16 - 17​	—​	—​	—​	Not Occupied​	—​	—​
18​	0.35​	GY / GN​	1102​	Low Speed GMLAN Serial Data 2​	I​	—​
19 - 27​	—​	—​	—​	Not Occupied​	—​	—​
28​	0.35​	WH / BU​	5986​	Serial Data Communication Enable​	I​	—​
29​	—​	—​	—​	Not Occupied​	—​	—​

 

[sir3lit]

The other connector has Left Rear Speaker [-] Control on Pin 8...

Pin​	Size​	Color​	Circuit​	Function​	Terminal Type ID​	Option​
1​	0.75​	RD / WH​	6440​	Battery Positive Voltage​	II​	—​
2​	0.75​	RD / WH​	6440​	Battery Positive Voltage​	II​	—​
3​	0.75​	BK / WH​	151​	Signal Ground​	II​	UQ3​
4 - 5​	—​	—​	—​	Not Occupied​	—​	—​
6​	0.75​	BK / WH​	251​	Signal Ground​	II​	UQ3​
7​	—​	—​	—​	Not Occupied​	—​	—​
8​	0.75​	GN / BK​	116​	Left Rear Speaker [-] Control​	II​	UQ3​
9​	0.35 0.35​	GY / YE BU​	5149 655​	Voice Recognition Audio Signal Cellular Telephone Microphone Signal​	I I​	UE1/ UER - UE1- UER​
10​	0.35 0.35​	BK / GY BK / BN​	5152 654​	Voice Recognition Audio [-] Control Cellular Telephone Microphone Low Reference​	I I​	UE1/ UER - UE1- UER​
11​	0.35​	VT / YE​	7043​	Microphone [+] Signal​	I​	—​
12​	0.35​	BU / BK​	7044​	Microphone [-] Signal​	I​	—​
13 - 29​	—​	—​	—​	Not Occupied​	—​	—​