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I ran this problem through the audio section without any results...still chasing
2002 Coupe... New DD Android Aftermarket HU front BOSE subs (both at same time blowing out).. losing bass....Door Amps/Subs cutting out randomly
Wired HU to Pac Roem-vet1..tuned the pots on PAC. buttoned everything up.
Music plays fine and sounds great for awhile (30 mins) then the front speakers lose their bass.
I have to cycle the key off/on or shut down the car for a few minutes and restart for the subs comes back on right away for a shorter time... then goes out again.
All worked fine with factory radio for years..right up to the day i switched head units...
Anyone have an idea whats going on? ...all new HU and Pac Roem
*I replaced the PAC module with a new one..same results...all connections are soldered tight/heatshrink and correct..double checked
* I swapped in a new relay in the footwell box...no change
* fuse 28 is good
*adjusted the front pots on the pac to try many different locations...all locations from 9am-2pm...no change
I would appreciate any help in running this one down...before i rip out the entire factory stuff..
I'm far from an expert on this, but you don't seem to be getting a lot of replies, so I'll give it a shot. It sort of sounds like you might be overtaxing your electrical system.. Could be as simple as dropping in an Optima yellow top. Maybe check to make sure that all your grounds are clean. You've already done everything that I would have suggested, so I'm kinda grasping at straws here.
I'm far from an expert on this, but you don't seem to be getting a lot of replies, so I'll give it a shot. It sort of sounds like you might be overtaxing your electrical system.. Could be as simple as dropping in an Optima yellow top. Maybe check to make sure that all your grounds are clean. You've already done everything that I would have suggested, so I'm kinda grasping at straws here.
Valid point regarding the C5 electrical system..i did clean and inspect "most" of the ground locations and i have a 3yrs Diehard Gold which is working properly.
I just cant see how a simple head unit swap would demand more current..enough to blow out the subs anyways?
im going to swap in a different aftermarket HU when i get some decent weather and see what that brings...
I have answered these questions many times..so here goes. I had pretty much the same problem. I believe its the PAC..it just doesn't work well with the Bose subs..although some do have success. I gave up..ripped it all out and put in focal component speakers. Bough the mounting plate off I think Southern car parts and just mounted it in the doors no problem. Sound deadened everything I could and ...Bazinga..nice sound. Then added a sub ..because you can't listen to heavy metal without one. I used an Alpine head unit and inline 50 watt Alpine amp which helps when driving component speakers..but you can try it with the head unit alone and then add an amp. Alpine makes a small one that fits right under the radio.
My initial thought was that you were overdriving the amp in the HU because of the low resistance Bose speakers. I read the comment above about the PAC having issues. I used the Axxess so I don't have PAC first hand knowledge. But I have seen radios shut down over the years because the internal amps were being over-driven by powering low impedance speakers. Then they need to be turned off or turned down and they reset. I would ask if it happens if you are running at a higher volume for a period of time. If it does, does it happen is running lower volumes or does it take longer to occur at lower volumes? That would indicate it's the HU turning off to protect itself.
Just a couple of thoughts.
Last edited by Ed Ramberger; 11-21-2020 at 10:08 PM.
Is your head unit dimming at all when the bass hits as it sits now? If yes then it's charging system related if not then it's a general electrical issue.
It is important to note that the Bose speakers are 2 ohm, most aftermarket head units are rated at 4 ohm per channel. 2 ohm speakers will tax the head unit by pulling more power than the head unit is rated for and may send it into protection mode after some period of time. After a cool down period it will start working again. Always replace the 4 standard Bose speakers when you do a head unit upgrade. They are junk anyway and you'll be doing yourself a favor.
My initial thought was that you were overdriving the amp in the HU because of the low resistance Bose speakers. I read the comment above about the PAC having issues. I used the Axxess so I don't have PAC first hand knowledge. But I have seen radios shut down over the years because the internal amps were being over-driven by powering low impedance speakers. Then they need to be turned off or turned down and they reset. I would ask if it happens if you are running at a higher volume for a period of time. If it does, does it happen is running lower volumes or does it take longer to occur at lower volumes? That would indicate it's the HU turning off to protect itself.
Just a couple of thoughts.
That makes perfect sense..
i thought from the start that this was a heat related issue the way both subs shut down at the same time... i have not kept note of time on/shut off as it relates to volume... pretty much same volume all the time (not cranked) lasts about 20 mins before the cut off
Is your head unit dimming at all when the bass hits as it sits now? If yes then it's charging system related if not then it's a general electrical issue.
It is important to note that the Bose speakers are 2 ohm, most aftermarket head units are rated at 4 ohm per channel. 2 ohm speakers will tax the head unit by pulling more power than the head unit is rated for and may send it into protection mode after some period of time. After a cool down period it will start working again. Always replace the 4 standard Bose speakers when you do a head unit upgrade. They are junk anyway and you'll be doing yourself a favor.
Have not noticed the HU dim at any time.
When you say replace the 4 bose speakers.... replace the 2x 3.5 in the door and the 2x 6.5 in the rear with 4ohm speakers?
Have not noticed the HU dim at any time.
When you say replace the 4 bose speakers.... replace the 2x 3.5 in the door and the 2x 6.5 in the rear with 4ohm speakers?
You'll need 1x Metra 72-4568 for the rear speakers and these for your new fronts at minimum. You need the bass blockers because of how the PAC harness gets its signal and passes it through. Without them your door subs will act like the 3.5 in door speakers and not make any bass. I recommend a set of these for your new rear speakers as well but that's up to you. You don't have to use these exact ones but I have found that they are the easiest to deal with and quickest way to do the job.
When it comes to speakers, personally I try to always steer toward textile tweeters instead of metallic because they sound less harsh to my ears. Generally you have to spend a little more to get textile tweeters though so yeah. Just depends on you and your budget. Another thing to keep in mind is that most 3.5 in speakers are rated at less than 20 watts RMS and if your head unit makes more it might be a good idea to look around and make sure you are getting speakers that will handle the load. For the best sound try to get speakers from the same manufacturer at a minimum and ideally from the same "range" or lineup of the same manufacturer. This will ensure proper tone matching and sound the best.
What I mean is if say the same maker has a G, GT, and GTX line don't get fronts from the GTX line and the rears from the G line if possible. If the G line has metal tweeters and the GTX line has silk for instance your high notes are gonna clash and you'll definitely notice the difference.
You'll need 1x Metra 72-4568 for the rear speakers and these for your new fronts at minimum. You need the bass blockers because of how the PAC harness gets its signal and passes it through. Without them your door subs will act like the 3.5 in door speakers and not make any bass. I recommend a set of these for your new rear speakers as well but that's up to you. You don't have to use these exact ones but I have found that they are the easiest to deal with and quickest way to do the job.
When it comes to speakers, personally I try to always steer toward textile tweeters instead of metallic because they sound less harsh to my ears. Generally you have to spend a little more to get textile tweeters though so yeah. Just depends on you and your budget. Another thing to keep in mind is that most 3.5 in speakers are rated at less than 20 watts RMS and if your head unit makes more it might be a good idea to look around and make sure you are getting speakers that will handle the load. For the best sound try to get speakers from the same manufacturer at a minimum and ideally from the same "range" or lineup of the same manufacturer. This will ensure proper tone matching and sound the best.
What I mean is if say the same maker has a G, GT, and GTX line don't get fronts from the GTX line and the rears from the G line if possible. If the G line has metal tweeters and the GTX line has silk for instance your high notes are gonna clash and you'll definitely notice the difference.
Thanks for the info and links to the wire harnesses...
After reading a few threads here..I was looking at these 3.5's for the doors..
Also..you said the factory speakers are 2 ohm and from what i read here they are all 4ohm in the C5 Corvettes?
If the factory are 4ohm...same power draw from HU with new...no fix...
For the life of me I don't remember who I talked to about the Vettes speakers and the 2 ohm rating. I'm 100% sure it was from someone here though but after a lot of forum and PM searching I am coming up empty. I know the Bose system in my Yukon uses all kinds of funky rated speakers though. It might be my confusion.
If it was one side or the other I'd say you had an amp going bad but if both subs are turning off then...it's gotta be something in common between them. That leaves your head unit and PAC harness. You said you double checked the harness which only leaves the head unit as a possible cause. Can you still exchange the head unit by any chance? Might be worth a shot. The issue you describe sounds exactly like some protection circuit in your head unit isn't happy with something, it might just be a faulty head unit.
For the life of me I don't remember who I talked to about the Vettes speakers and the 2 ohm rating. I'm 100% sure it was from someone here though but after a lot of forum and PM searching I am coming up empty. I know the Bose system in my Yukon uses all kinds of funky rated speakers though. It might be my confusion.
If it was one side or the other I'd say you had an amp going bad but if both subs are turning off then...it's gotta be something in common between them. That leaves your head unit and PAC harness. You said you double checked the harness which only leaves the head unit as a possible cause. Can you still exchange the head unit by any chance? Might be worth a shot. The issue you describe sounds exactly like some protection circuit in your head unit isn't happy with something, it might just be a faulty head unit.
I have read in a few places that the C5 Factory speakers are 4 ohms and the door subs are 1 Ohm
I've had the HU too long now to return anywhere..im going to swap in another HU to test when i get some decent weather (too cold now).
Also going to look into bypassing the HU internal amp somehow?
Thanks for your input..much appreciated
I have read in a few places that the C5 Factory speakers are 4 ohms and the door subs are 1 Ohm
I've had the HU too long now to return anywhere..im going to swap in another HU to test when i get some decent weather (too cold now).
Also going to look into bypassing the HU internal amp somehow?
Thanks for your input..much appreciated
I have read values all over the board. I just measured the OE 3.5" front door and 5.25" vert rear speakers and got between 3.2 and 3.5 ohm.
Last edited by Ed Ramberger; 11-23-2020 at 03:27 PM.
All this is a lot of work just to keep the crappy Bose woofers. Much easier to just use component speakers. Focal makes good ones and you can get a plate premade to mount them and the crossover. Its best to run an amp with these as stock headunits never put out much power.
10-11-2020, 04:46 PM
Electrical? Door Subs turning off randomly
