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Discussion Starter #1
I have the ms-8 input harness soldered up. I am not getting a signal according to the ms-8, but I did the last time it was hooked up (I had a bad amp that I had to swap out).

So, I have unplugged the harness from the ms-8...how do I use my multimeter to see if my head unit is actually sending a signal through the plug?



I think this is the first logical place to start troubleshooting.

Thank you...


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Try burning a cd with a sine wave tone.. or download an mp3 of it to your ipod/mp3 player. You can bet free tone generators on the web. Just google.
200hz or so would do the trick.

Then use the dvm to measure the voltage.. vary the volume. you should be able to get 500 mv AC easily
 

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Discussion Starter #3
I've got test tones avail. Focal disc number two. :)

Where do I put my test leads? These are balanced differential, if it matters. So, just set the dmm to DCV and put red to pos+ and black to neg- and look for ~500 milliamperes with the HU vol cranked up using a 200 HZ signal or sine wave?


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It's not clear to me in your post if you're doubting the integrity of your harness or unit. If you're checking the integrity of your solder job, switch your DMM to the continuity feature. Put a probe on each end of the connection, and verify if there is continuity.

I have a Fluke DMM, and mine beeps if there is continuity.

Hope this helped.
 

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Discussion Starter #6
It's not clear to me in your post if you're doubting the integrity of your harness or unit. If you're checking the integrity of your solder job, switch your DMM to the continuity feature. Put a probe on each end of the connection, and verify if there is continuity.

I have a Fluke DMM, and mine beeps if there is continuity.

Hope this helped.
Here's the deal...
1) I have a BMW Harman Kardon system that has ext amp. I bypassed that amp by intercepting the wires prior to the amp and running the balanced inputs via soldered extension wires to the trunk. This was a long time ago with my old setup -- loc, two alpine amps, etc. Outstanding results. Was happy, but not happy enough! Lol

2)Went to the ms-8 and a Massive Audio nx5 five-channel amp. Everything was working great for a few days, then the amp went into protection and never came out of protection. Told to send it back...this is apparently not uncommon. Said, forget massive, and replaced it with An Arc Audio 5-ch.

3) swapped out the amp and expected everything to be fine. But the initialization of the ms-8 looks for a signal from the HU, which it's not getting. Now, considering none of that end of the build was changed, this confuses me. Why isn't it getting a good signal now when it did before. This is all prior to the amp; at this stage I probably don't even need an amp hooked up.

4)I set my Dvm to dcv and put the red on pos at the plug and black on neg at the plug. I got 148 mv, I think. I'm gonna have the wife help me out so I can get a better reading.
I'll repost my results in 30 minutes or less.

5) I don't want to tear the car apart to check the solder connections if I don't have to. If I'm getting a good signal to the plug, then the ms-8 has problems and I'm screwed. :(





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Discussion Starter #7
Showing acv of .036, dcv of like 146 cranked up and 141 turned down. These numbers don't seem right to me...
I'm so frikkin frustrated right now!!


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Discussion Starter #8

1) Pulled everything apart. Got that reading off of the lugs of the barrier strip itself (these are the FRONT speaker high volts from the HU); that's where the OEM wires start to get rerouted back to the ms-8. It was like 173 mV on DCV auto. Didn't seem to go down or up much with my volume control knob, maybe 5 points or so.

2) checked continuity between that lug and the plug end, good. Checked reading at plug, 173 again, consistent.

3) checked REAR lugs, 4 VOLTS. So, I'm seeing the rear speaker outs from the factory HU put out 4 volts but the front speaker outs put out .173 volts.

4) is is possible to fry the front channels? If I use the rears, am I going to fry them too? BMW radios probably aren't cheap, even used on eBay! Lol

Help, help, help...




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Sorry you're so frustrated, I hope I can help.

1) Use AC volts for measuring audio signals both line level (0-8v ac, usually closer to 2v though) and speaker level (about 5-15v ac at moderate volumes). If you use DC on your volt meter you'll not get anywhere. DC is used for measuring the voltage coming from your alternator, battery, and going to your radio and amplifier via the large fused red cable.

2) Is your factory radio faded to the rear speakers or are there any other settings that would mute the fronts? It's a long shot, but the simple things are always easy to check.

You're doing the right things by searching for a voltage coming from the factory radio front outputs. Troubleshooting is all about trying to isolate a failure by removing variables until only a few remain (the MS-8, the wire from the MS-8 to the terminal strips, the terminal strips, the wire from the terminal strips to the solder joint, and the solder joint where you tap into the factory wiring are all examples of variables). The important thing to remember is when you test at a point closer to the factory radio, you must remove everything downstream of that point. I mean when you test at the terminal strips, you must remove all wiring and connections that go from the strips to the MS-8.

3) Try to go as far upstream as you can on the factory radio front output wires for testing (and disconnect everything downstream of your testing point). The soldering job you did "a long time ago" would be a good place to try. If you can un-solder both of your + and - wires at that point and test the car's factory wiring with nothing else attached to them, you can isolate the problem to either upstream of that point (factory radio might be a possibility) or something downstream (your wiring, terminal block, the MS-8, etc).

Good luck, I'll help again if I can.

-J
 

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just a couple of things. 5-15 volts on a HU or PA high level speaker output is quite alot.
5 volts would be about 6 watts into 4 ohms and 15 volts AC RMS would be over 50 watts. you probably wont get that from any factory HU!

have you considered that the MS8 is faulty? if it was your amp that stopped working, with the MS8 inbetween, why should any HU to MS8 wiring have gone bad all of a sudden?
Trouble shooting first means trying to isolate different parts and testing them separately. Checking things that are easy to test first. Ripping out wiring is hard work and usually not the immediate cause of failure.

So, first test the outputs from your HU by connecting your HU outputs directly to your amp, bypassing the MS8.. Use low volume!

Did you try to reset your MS8?

Or use your mp3 player and connect to your MS8 to test it independently of you HU outuputs.
 

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Discussion Starter #11
Sorry you're so frustrated, I hope I can help.

1) Use AC volts for measuring audio signals both line level (0-8v ac, usually closer to 2v though) and speaker level (about 5-15v ac at moderate volumes). If you use DC on your volt meter you'll not get anywhere. DC is used for measuring the voltage coming from your alternator, battery, and going to your radio and amplifier via the large fused red cable.
I really, REALLY appreciate it.
Ok, about to go to the garage and begin troubleshooting again. I'll use ACV. I'll post my results.

2) Is your factory radio faded to the rear speakers or are there any other settings that would mute the fronts? It's a long shot, but the simple things are always easy to check.
I agree with that! No, everything has been double checked and centered and flat; system doesn't have any factory eq, DSP, etc to be defeated.

You're doing the right things by searching for a voltage coming from the factory radio front outputs. Troubleshooting is all about trying to isolate a failure by removing variables until only a few remain (the MS-8, the wire from the MS-8 to the terminal strips, the terminal strips, the wire from the terminal strips to the solder joint, and the solder joint where you tap into the factory wiring are all examples of variables). The important thing to remember is when you test at a point closer to the factory radio, you must remove everything downstream of that point. I mean when you test at the terminal strips, you must remove all wiring and connections that go from the strips to the MS-8.
I did that last night, for the first time. I have all the factory wires going to the barrier strips, then from the barrier strips to external processing/amplification, then from there BACK to the terminal strips to get reintegrated with the OEM wiring. I pulled the wires that go from factory output ---> ms-8 input, then checked the OEM output, but I used DCV. I understand audio, but not electricity. I played with changing things around, using the rears, the fronts, switching pos/neg, etc. Couple hours worth. It's fairly easy because of the barrier strips, so I went crazy (almost literally). The ms-8 never got a signal. SIGNAL NONE.

3) Try to go as far upstream as you can on the factory radio front output wires for testing (and disconnect everything downstream of your testing point). The soldering job you did "a long time ago" would be a good place to try. If you can un-solder both of your + and - wires at that point and test the car's factory wiring with nothing else attached to them, you can isolate the problem to either upstream of that point (factory radio might be a possibility) or something downstream (your wiring, terminal block, the MS-8, etc).
That was very easy with the barrier strips. I was able to pop anything and everything away from the OEM HU output leads. The solder joints are good. The plug at one end and the spade lug at the other end (connects to barrier strip) have strong continuity, at all four: FL+, FL-, FR+ FR- that converts to ch1+/-, ch2+/- at the ms-8.

Good luck, I'll help again if I can.

-J
Thank you, I have the feeling I'll need it.

Here is what kept me awake last night:

1) the only thing that changed from setup with NX5 and now is the NX5 ---> Arc Audio amp change. This should have been a 30-min swap out.

2) unrelated (maybe) but, when using the DVM, I noticed that some of my readings, when red on pos and black on neg, displayed a "-" before the reading, indicating that my leads were reversed, right? So it's possible that either the BMW wiring guide I used was wrong to some degree, or someone at BMW connected the wires in reverse. BOTH seem unlikely, and it's sort of irrelevant if you re-read #1 above. The ms-8 worked great with the wires the way they were.
However, I wonder how the ms-8 reacts to the pos and neg being mixed up at the input, if that were the case? But again...#1...!




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Discussion Starter #12
just a couple of things. 5-15 volts on a HU or PA high level speaker output is quite alot.
5 volts would be about 6 watts into 4 ohms and 15 volts AC RMS would be over 50 watts. you probably wont get that from any factory HU!
Yeah, I don't know very much about electricity. I am not completely ignorant to it, I can do home wiring, install a hot water heater, install a sprinkler system, or 220v pool timer...but if you put any of those things into a car...lol
I need to retest using ACV.

have you considered that the MS8 is faulty? if it was your amp that stopped working, with the MS8 inbetween, why should any HU to MS8 wiring have gone bad all of a sudden?
I have considered that. That scares the crap out of me 'cause I don't have any warranty. But I have a gut feeling that it isn't the ms-8. Things to consider:
- Maybe the NX5 was in protection because of the ms-8. ?
-However, the ms-8 will play through my new amp if I skip input setup, set up all my crossovers, etc. it sends the pink noise test signal just fine around all my channels/speakers.
- it worked fine before.

Trouble shooting first means trying to isolate different parts and testing them separately. Checking things that are easy to test first. Ripping out wiring is hard work and usually not the immediate cause of failure.
Well, I knew I was going to have to eventually so I just went ahead and pulled the wiring block out into the daylight! It's very easy to test things the way I have it set up...I just don't know what to look for! Lol

So, first test the outputs from your HU by connecting your HU outputs directly to your amp, bypassing the MS8.. Use low volume!
Can't, the amp doesn't accept speaker leads. I DO have an AudioControl LOC I can use if I have to. Saving that option for last; I don't need any more variables at this point, don't really have room for the LOC, and the ms-8 should be able to do the same thing...it just isn't for some reason.

Did you try to reset your MS8?
Yes, I reset it physically and via software through the "reset to system defaults" or something like that though the remote.

Or use your mp3 player and connect to your MS8 to test it independently of you HU outuputs.
To do that, I have to finish the entire setup, including the headphone mic measurements, right?

Thank you for taking the time to try to help, I appreciate it very much.




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Yeah, I don't know very much about electricity. I am not completely ignorant to it, I can do home wiring, install a hot water heater, install a sprinkler system, or 220v pool timer...but if you put any of those things into a car...lol
I need to retest using ACV.



I have considered that. That scares the crap out of me 'cause I don't have any warranty. But I have a gut feeling that it isn't the ms-8. Things to consider:
- Maybe the NX5 was in protection because of the ms-8. ?
-However, the ms-8 will play through my new amp if I skip input setup, set up all my crossovers, etc. it sends the pink noise test signal just fine around all my channels/speakers.
- it worked fine before.



Well, I knew I was going to have to eventually so I just went ahead and pulled the wiring block out into the daylight! It's very easy to test things the way I have it set up...I just don't know what to look for! Lol



Can't, the amp doesn't accept speaker leads. I DO have an AudioControl LOC I can use if I have to. Saving that option for last; I don't need any more variables at this point, don't really have room for the LOC, and the ms-8 should be able to do the same thing...it just isn't for some reason.



Yes, I reset it physically and via software through the "reset to system defaults" or something like that though the remote.



To do that, I have to finish the entire setup, including the headphone mic measurements, right?

Thank you for taking the time to try to help, I appreciate it very much.




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if you do home wiring etc then you should know what ac and dc is. and that audio signals are ac.. and you should also be able to do simple ohms law and voltage, power calculations. If no.. I suggest you stay away from home wiring..

and yes you have to redo the entire MS8 calibration.. it sucks I know.. there should be a quick bypass. just connect inputs and play.. just for trouble shooting purposes. Hope they do that in a sw upgrade.
Any car audio geek should have some speaker level to rca converters hanging around in the parts bin... even cheap cheap ones! for trouble shooting purposes

just to let you know.. I have had difficulty getting the MS8 to recognise low level imputs too. I broke input #1 and tried to use other inputs but it would not recognise them. said signal found but too low level. Other users have succeeded in having the MS8 recognise other low level inputs.
 

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Discussion Starter #14
Ok just did some checks with ACV, with test tone at 250hz:

- fronts connected to ms-8, 0.000 at front, rears 0.010 not connected to anything

- disconnected the wires going to the ms-8, did it again; fronts 0.006. Then I "spun" the volume control about 5 times, which would easily max out the HU on the first or second spin, and tried it again.
(Now keep in mind that when I get the SIGNAL NONE message, I spin this same volume control over and over again with no change. I also had my wife maxing it out when I first took my measurements.)
But this time, the signal got boosted...it went to 0.055 on both channels. Then I tried it again after a few minutes and got 0.049. Then I hooked it back up to the ms-8 and got frikkin' ZERO again. Ugggghhhhh!

(I actually made videos to put on YouTube for you guys to see, but forgot that on Friday my cable modem went t/u)

- set the whole thing up using just the ms-8, changed input to aux, plugged in my phone and bam, plays like a champ! Sounds fantastic, even not tweaked. So, I'm assuming the ms-8 works, and my new amp works.
You think maybe I fried my radio somehow? I was using the ms-8 at Static -6 volume and then using my radio/steering wheel controls for volume adjustment, so it wasn't that I was running the radio "wide open" all the time (2 days at least while nx5 amp was working).

Hell I don't know...anything.




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Yeah, I don't know very much about electricity. I am not completely ignorant to it, I can do home wiring, install a hot water heater, install a sprinkler system, or 220v pool timer...but if you put any of those things into a car...lol
I need to retest using ACV.



I have considered that. That scares the crap out of me 'cause I don't have any warranty. But I have a gut feeling that it isn't the ms-8. Things to consider:
- Maybe the NX5 was in protection because of the ms-8. ?
-However, the ms-8 will play through my new amp if I skip input setup, set up all my crossovers, etc. it sends the pink noise test signal just fine around all my channels/speakers.
- it worked fine before.



Well, I knew I was going to have to eventually so I just went ahead and pulled the wiring block out into the daylight! It's very easy to test things the way I have it set up...I just don't know what to look for! Lol



Can't, the amp doesn't accept speaker leads. I DO have an AudioControl LOC I can use if I have to. Saving that option for last; I don't need any more variables at this point, don't really have room for the LOC, and the ms-8 should be able to do the same thing...it just isn't for some reason.



Yes, I reset it physically and via software through the "reset to system defaults" or something like that though the remote.



To do that, I have to finish the entire setup, including the headphone mic measurements, right?

Thank you for taking the time to try to help, I appreciate it very much.




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Ok just did some checks with ACV, with test tone at 250hz:

- fronts connected to ms-8, 0.000 at front, rears 0.010 not connected to anything

- disconnected the wires going to the ms-8, did it again; fronts 0.006. Then I "spun" the volume control about 5 times, which would easily max out the HU on the first or second spin, and tried it again.
(Now keep in mind that when I get the SIGNAL NONE message, I spin this same volume control over and over again with no change. I also had my wife maxing it out when I first took my measurements.)
But this time, the signal got boosted...it went to 0.055 on both channels. Then I tried it again after a few minutes and got 0.049. Then I hooked it back up to the ms-8 and got frikkin' ZERO again. Ugggghhhhh!

(I actually made videos to put on YouTube for you guys to see, but forgot that on Friday my cable modem went t/u)

- set the whole thing up using just the ms-8, changed input to aux, plugged in my phone and bam, plays like a champ! Sounds fantastic, even not tweaked. So, I'm assuming the ms-8 works, and my new amp works.
You think maybe I fried my radio somehow? I was using the ms-8 at Static -6 volume and then using my radio/steering wheel controls for volume adjustment, so it wasn't that I was running the radio "wide open" all the time (2 days at least while nx5 amp was working).

Hell I don't know...anything.




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some sort of muting on your HU? this is odd. Did you try disconnecting power from the HU? maybe a reset?
 

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Discussion Starter #16 (Edited)
some sort of muting on your HU? this is odd. Did you try disconnecting power from the HU? maybe a reset?
Radio doesn't have muting but does have bluetooth...

Actually, I did, because I checked both of the fuses ealier in the process.

I did do some work on the car in between amps, and the ms8 and amp board were out of the car: I ran a new amp ground, and i ran a better quality aux input cable to the front of the car (but never got behind the dash or anything like that, just fished it along the center console). I didn't even consider any of this since it's so far removed from my problem. However, I wonder if somehow I disrupted the OEM radio ground wire. I really don't think so, but it does make sense. If the radio has an intermittant "good" ground mixed with a "mediocre" ground, that might, might explain it giving me power, then not giving me power. That's my next thing to check at least. :confused:

I'm at work, and I am uploading the videos. I'll link them here when they get done, about 15 more minutes.
 

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Discussion Starter #20
Before I left for work, I took some interconnects and cut one end off, soldered up some spades and tried running the ms8 that way. It worked. Thats good news, but doesn't solve my problem, really. With this method, I don't get the benefit of un-eq'ing the system, and I worry about overloading the system at the RCAs if my connection "fixes itself" (if it is some sort of loose connection somewhere).

I guess I could use the LOC...
 
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