Rep Power: 0

Hey guys - im losing my mind over here. I have a 2005 civic ex sedan and this all started when the stock radio threw a code. i figured id just replace the head unit. I got a cheap blaupunkt stereo but I dont think thats the issue. First things first the rear speakers dont work at all. wiring looks good but i haven't checked for a short. I tried switching positive and negative to see if the polarity was reversed and tried tying the rear speakers into the front speaker wires and still nothing. figured front speakers were fine for now until i could investigate more and now the head unit wont power on. whats going on? do I have a ground issue? a short somewhere? I also saw some posts of people tying the blue antenna wire into another - whats that about?

The wiring in my car is the left and the blaupunkt is the right (Application. | Honda Stock Color | Blaupunkt wire):
+12V DC Battery(Constant) | WHITE/ red | Yellow
Switched Accessory | Yellow/red | Red
Ground | Black | Black
Dimmer | Red | no match to connect- capped.
Illumination | RED / black | no match to connect - capped.
Left Front + | GREEN/ black | White
Left Front - | Light green | White/Blk Stripe
Right Front + | GREEN/ YELLOW | Gray
Right Front - | Gray/red | Gray/Blk
Left Rear + | Blue/white | Green
Left Rear - | Blue/black | Green/Blk
Right Rear + | Pink | Purple
Right Rear - | Blue / YELLOW | Purple/Blk
Power Antenna | N/A capped | Blue

 
Rep Power: 125

Why didn't you use a harness adapter? Chances are one of your connections are bad (I'm guessing rear speakers are one of them). And yes, it's possible that a cheap radio could cause problems too.

 
Rep Power: 511

Moved to 7thgen section.

Will update when I find wiring diagram. The dimmer wire should be the only one looped off and connected to nothing.

edit: wait. did you cut the factory harness off and direct wire the blaupunkt harness to the factory wiring? Or did you grab something like a metra harness?

 
Rep Power: 0

I wired direct not using a metra harness. there was a harness that came with the radio so I used butt connectors to splice them together.

 
Rep Power: 125

I'm betting that's your problem. Harness adapters are only like $10 and make it so much easier.

 
Rep Power: 0

Im not an expert level wire splicer for sure, and this was my first thought also. I opened it all back up and checked the rear speaker wires and redid the connection just to be sure and they still wouldnt work.

 
Rep Power: 0

I agree that would have been easier, but I checked all the connections and they all seem secure. I redid the rear speaker ones just in case and still nothing.

 
Rep Power: 0

I wired it direct.

 
Rep Power: 0

Update: I fixed the stereo but the rear speakers are still not working. I used a voltmeter on the rear speakers and one showed no current the other showed 3.6 ohms. my logic was then - ok one speaker is dead but one should still be working so the working speaker must have a short in the wire somewhere. to test this theory i swapped the harnesses to the rear speaker thinking "what are the chances both sets of wiring are shorted" and still nothing. so either the rear speaker wires are both shorted out somewhere or theres a hidden amp for the rear speakers somewhere I don't know about thats not plugged in now that I replaced the stereo, or???? idk. butt splices to the stereo are solid. any ideas?

 
Rep Power: 209

Are you sure the rear speakers work? The original speaker are crap and when they sit in the sun the cones are destroyed. When I replaced mine years ago they barely made a sound and when I took them out it was obvious why.

 
Rep Power: 0

I'm not positive. the cones seem intact and theres no apparent water damage in that area either. All I know is that there seemed to be some current in the back right speaker when I used my multimeter but not the back left. I switched the wiring harnesses that attached directly to the speakers to see if I could get some sound but no luck. theres zero sound coming through the speakers.

 
Rep Power: 242

If you were reading 3.6 ohms you were reading resistance not current. The speaker should give you a resistance reading if the coil is good.

Try plugging a rear speaker into the front.

 
Rep Power: 0

Reached out to someone on another thread who had his head unit code and rear speakers were not working after. He said his rear speakers died when that happened and it was an easy fix. I dont know why the stereo would just insta-kill both speakers, but i did replace the battery the weekend before so maybe something happened in relation to that. Ill replace the speakers and hope all goes well! Ill give a final update to everyone once they are in this weekend

 
Rep Power: 511

I'm glad that 1) I was able to find that link so you can reach out and 2) you actually got a response from that user. Did not see that coming at all, truth be told.

This right here is why I help people; for the guys and girls out there willing to post up and help future people out.

 
Rep Power: 0

you're the best!

 
Rep Power: 0

Final update: yes, when I changed the battery in the car it made the stereo code and killed both of the rear speakers. No idea why that happened, but replaced the head unit and the rear speakers and everything is as good as new. Found a post that said they didn't need to replace the head unit and just entered the code and replaced the rear speakers and everything worked for them. Hope this helps someone out so they don't waste time checking their wiring 3 times over like I did. If anyone wants to chime in with why they think changing the battery in the car does this I would be curious to know.

 
Rep Power: 118

Factory rear speakers in my Civic died completely years ago..
Needing a code for the radio after losing power likely saved millions of owners the hassle of dealing with broken windows and torn up dashes.