Bose very quiet
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 48
Likes: 7
From: Vancouver BC
Bose very quiet
Hey guys,
Hoping for some wisdom here before I go out buying a new CDM for my '90 ZR-1.
When I first got the car there was no sound out of the sound system whatsoever. I went to the junkyard, got 4 nissan/infiniti Bose amps and put them in (my old ones were definitely fried, capacitors leaked all over the place)
Now I have lovely clear sound out of all 4 speakers...but only if I crank the volume up to max can I make it out, and even then only if the car is off. Is there a simple thing I'm missing somewhere, or am I looking at replacing the CDM box next? Is there an easy test I can do?
Thanks in advance
Hoping for some wisdom here before I go out buying a new CDM for my '90 ZR-1.
When I first got the car there was no sound out of the sound system whatsoever. I went to the junkyard, got 4 nissan/infiniti Bose amps and put them in (my old ones were definitely fried, capacitors leaked all over the place)
Now I have lovely clear sound out of all 4 speakers...but only if I crank the volume up to max can I make it out, and even then only if the car is off. Is there a simple thing I'm missing somewhere, or am I looking at replacing the CDM box next? Is there an easy test I can do?
Thanks in advance
Oil Producer
Joined: Apr 2014
Posts: 9,364
Likes: 2,734
Hey guys,
Hoping for some wisdom here before I go out buying a new CDM for my '90 ZR-1.
When I first got the car there was no sound out of the sound system whatsoever. I went to the junkyard, got 4 nissan/infiniti Bose amps and put them in (my old ones were definitely fried, capacitors leaked all over the place)
Now I have lovely clear sound out of all 4 speakers...but only if I crank the volume up to max can I make it out, and even then only if the car is off. Is there a simple thing I'm missing somewhere, or am I looking at replacing the CDM box next? Is there an easy test I can do?
Thanks in advance
Hoping for some wisdom here before I go out buying a new CDM for my '90 ZR-1.
When I first got the car there was no sound out of the sound system whatsoever. I went to the junkyard, got 4 nissan/infiniti Bose amps and put them in (my old ones were definitely fried, capacitors leaked all over the place)
Now I have lovely clear sound out of all 4 speakers...but only if I crank the volume up to max can I make it out, and even then only if the car is off. Is there a simple thing I'm missing somewhere, or am I looking at replacing the CDM box next? Is there an easy test I can do?
Thanks in advance
subbed
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
The CDM is a low level output device (like a pre-amp). It drives the Bose speaker boxes which are amplified speaker boxes which makes the signal (voltage) increased so it can drive the speaker with enough power. If you don’t have amplified speaker boxes and are just trying to drive the speakers directly from the CDM, then there is not enough power (drive) for the speakers and won't be louder enough.
Of course the whole system is a miss-match for impedance since the CDM is not designed to drive a low resistance coil (voice coil of the speaker).
Bottom line is you have the wrong part (speakers) in there.
Of course the whole system is a miss-match for impedance since the CDM is not designed to drive a low resistance coil (voice coil of the speaker).
Bottom line is you have the wrong part (speakers) in there.
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 48
Likes: 7
From: Vancouver BC
The CDM is a low level output device (like a pre-amp). It drives the Bose speaker boxes which are amplified speaker boxes which makes the signal (voltage) increased so it can drive the speaker with enough power. If you don’t have amplified speaker boxes and are just trying to drive the speakers directly from the CDM, then there is not enough power (drive) for the speakers and won't be louder enough.
Of course the whole system is a miss-match for impedance since the CDM is not designed to drive a low resistance coil (voice coil of the speaker).
Bottom line is you have the wrong part (speakers) in there.
Of course the whole system is a miss-match for impedance since the CDM is not designed to drive a low resistance coil (voice coil of the speaker).
Bottom line is you have the wrong part (speakers) in there.
Nissan Maxima and Infiniti I30s between 95-99 had the same type of Bose speaker/amp with a very similar equalization. That's the car that I pulled these amps out of. I am fairly confident that's not the issue.
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 48
Likes: 7
From: Vancouver BC
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
According to various other threads (notably this one: http://www.zr1.net/forum/showthread.php?t=20380
Nissan Maxima and Infiniti I30s between 95-99 had the same type of Bose speaker/amp with a very similar equalization. That's the car that I pulled these amps out of. I am fairly confident that's not the issue.
Nissan Maxima and Infiniti I30s between 95-99 had the same type of Bose speaker/amp with a very similar equalization. That's the car that I pulled these amps out of. I am fairly confident that's not the issue.
If there is no 12 volts to the boxes, then you need to look at the Bose relay to see if its being energized (turned on) and voltage to the relay contacts so it can connect it to the speaker boxes.
Not sure on the "90" where the Bose relay definitely is but I think it is under the dash on passenger side.
Are the connectors (plugs) on the new boxes the same as the ones you took out?
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 48
Likes: 7
From: Vancouver BC
OK - Then the place to start is to measure the voltage to the speaker box and the ground also. Rather than using chassis ground, it would probably be ok to use the ground from cable bunch and reference the power (12 volts) to it. You also need a return line for the audio.
If there is no 12 volts to the boxes, then you need to look at the Bose relay to see if its being energized (turned on) and voltage to the relay contacts so it can connect it to the speaker boxes.
Not sure on the "90" where the Bose relay definitely is but I think it is under the dash on passenger side.
Are the connectors (plugs) on the new boxes the same as the ones you took out?
If there is no 12 volts to the boxes, then you need to look at the Bose relay to see if its being energized (turned on) and voltage to the relay contacts so it can connect it to the speaker boxes.
Not sure on the "90" where the Bose relay definitely is but I think it is under the dash on passenger side.
Are the connectors (plugs) on the new boxes the same as the ones you took out?
I've already tried replacing the Bose relay with a new one hoping for an easy fix (it's under the driver's side dash, beside the Fuel pump 2 relay for the ZR-1)
I tested when I was putting them in and the speakers are getting the 12V signal as expected. They do make sound, just not *enough* of it, which leads me to believe that there can't be an actual broken connection anywhere? I'm no expert though.
Thanks for your help! Keep the suggestions coming.
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Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Been repairing Bose speaker circuit boards for 15 years among other things in my career. Leaky capacitors don’t mean they are definitely bad. Most of the capacitors are de-coupling for power and cause hum or squealing. Only 1 cap is a coupling capacitor which causes low or muddy volume. (Not trying to give a lesson or boast, just some info). The likeliness of having 4 bad speaker boxes are real low.
So in reviewing you first post and all that has been done, it seems that after replacing the boxes and making the measurements the original problem is still in there and the 4 original speakers removed probably work OK or at least somewhat.
If the radio head seems to work A-OK with the visual indications, tape goes around and get some sound as well as CD player, it would seem to me to focus on the CDM itself for being the root cause of the problem. This is just my current surface opinion for the current conditions.
So in reviewing you first post and all that has been done, it seems that after replacing the boxes and making the measurements the original problem is still in there and the 4 original speakers removed probably work OK or at least somewhat.
If the radio head seems to work A-OK with the visual indications, tape goes around and get some sound as well as CD player, it would seem to me to focus on the CDM itself for being the root cause of the problem. This is just my current surface opinion for the current conditions.
Last edited by pcolt94; Mar 11, 2017 at 09:50 AM.
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 48
Likes: 7
From: Vancouver BC
Been repairing Bose speaker circuit boards for 15 years among other things in my career. Leaky capacitors don’t mean they are definitely bad. Most of the capacitors are de-coupling for power and cause hum or squealing. Only 1 cap is a coupling capacitor which causes low or muddy volume. (Not trying to give a lesson or boast, just some info). The likeliness of having 4 bad speaker boxes are real low.
So in reviewing you first post and all that has been done, it seems that after replacing the boxes and making the measurements the original problem is still in there and the 4 original speakers removed probably work OK or at least somewhat.
If the radio head seems to work A-OK with the visual indications, tape goes around and get some sound as well as CD player, it would seem to me to focus on the CDM itself for being the root cause of the problem. This is just my current surface opinion for the current conditions.
So in reviewing you first post and all that has been done, it seems that after replacing the boxes and making the measurements the original problem is still in there and the 4 original speakers removed probably work OK or at least somewhat.
If the radio head seems to work A-OK with the visual indications, tape goes around and get some sound as well as CD player, it would seem to me to focus on the CDM itself for being the root cause of the problem. This is just my current surface opinion for the current conditions.
So it sounds like the CDM is going to be what needs fixing. Are these repairable at all, or should I just scour fleabay for one?
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Here in the US and FL where I live there are car radio repair services who specialize in repairing Bose systems. But I could not tell you where they are where you live. There are repairable, just need to get to the right business who are geared up for these repairs.
Just on a chance make sure all connections at the plugs are not corroded and all the pins and connections to them look OK. While it's ON and you can hear a radio station, wiggle any wires you can get to that have anything to do with the radio and CDM, relay etc, tap around the CDM to see if it might pop on from an internal bad solder connection. If you were able to get your hands on a CDM for test, that would take a lot of the guess work out of the troubleshooting.
Just on a chance make sure all connections at the plugs are not corroded and all the pins and connections to them look OK. While it's ON and you can hear a radio station, wiggle any wires you can get to that have anything to do with the radio and CDM, relay etc, tap around the CDM to see if it might pop on from an internal bad solder connection. If you were able to get your hands on a CDM for test, that would take a lot of the guess work out of the troubleshooting.
Thread Starter
Intermediate
Joined: Oct 2015
Posts: 48
Likes: 7
From: Vancouver BC
Hey folks,
Sorry to bring my own post back from the dead, but thought I'd give an update for anyone else having the same issue.
I've been keeping my eye on ebay, and managed to recently pick up a used CDM for $100. Swapped it in today and bam, nice clear loud sound through all 4 speakers. I'm now a happy camper once more.
Cheers
Sorry to bring my own post back from the dead, but thought I'd give an update for anyone else having the same issue.
I've been keeping my eye on ebay, and managed to recently pick up a used CDM for $100. Swapped it in today and bam, nice clear loud sound through all 4 speakers. I'm now a happy camper once more.
Cheers
Racer
Joined: Jan 2020
Posts: 467
Likes: 47
I am having the same issue here. Music playing, but very, very quiet. Casette is playing, I can hear it, very low in volume.
Question: does this fix here (buy a new CDM) also apply if the issue is with the Casette?
Thanks
Question: does this fix here (buy a new CDM) also apply if the issue is with the Casette?
Thanks
Racer
Joined: Jan 2020
Posts: 467
Likes: 47