Amp output is 0v... :(

[gangstajpimpin 10+ year member]

I am wondering why my past two amps have been reading 0v on the output. I am pretty sure that all connections are ROCK SOLID. The RCA cables are good as well.

Input voltage at amplifier: 12.4v (car off), 11.2v (remote)

I know the amplifier isn't fried because the same thing happened to my alpine...could the subwoofer possibly be blown or....?

What lead up to this problem is listening to my music at full tilt for a long time, and i think i EQ'd the bass end a little high...

Thanks for your help!

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[mcsoul 10+ year member]

dmm on the subs? ohms?

I don't think the amp should need a load to put out voltage when

input signal is applied. Sounds like the sub out on your HU is off.

 

[gangstajpimpin 10+ year member]

sub out on headunit is on...i checked that yesterday lol!

will check with DMM after work

 

[mcsoul 10+ year member]

sub out on headunit is on...i checked that yesterday lol!
will check with DMM after work

Check the input voltage off the rca's, carefully don't short it.

 

[gangstajpimpin 10+ year member]

how do you check the voltage of RCA's??

 

[bw_audio 10+ year member]

..

 

[x1le 10+ year member]

Are you switched to AC when checking the output?

 

[gangstajpimpin 10+ year member]

Both the component RCA and sub RCA's showed no voltage, but i switched the rca's and the component speakers still worked so it cant be the RCA's...

I used a multimeter on my subwoofer. I set it to the diode symbol and attached the probes negative to negative, positive to positive. The reading was 1 on the DMM. So i think the Voice Coils might be blown on the sub??

Could that be the cause of a 0v output on the amplifier?

 

[darsum 10+ year member]

Both the component RCA and sub RCA's showed no voltage, but i switched the rca's and the component speakers still worked so it cant be the RCA's.....QUOTE]


were you using a test tone while measuring the (RCA) voltage outputs from your headunit? did you put the DMM selector at the AC portion? where was your HU vol., (and treble and bass level) set at?

if I can remember correctly, my alpine HU doesn't give a voltage reading until it reaches vol. 18 and above, (using my cheap DMM).

also, did you check on the RCAs themselves? Is there continuity?

 

[gangstajpimpin 10+ year member]

I was playing Young jeezy at about volume 15..haha...i will try to remeasure voltages. And i put it on the AC 250 setting...or was it AC 200...all i know is there was a setting for AC 750 or 200/250...cant remember

 

[Ferendon 10+ year member]

With the range that high, your DMM might not be able to read (or at least display) the 4v your head unit is putting out. Do you have a range button on your DMM?

 

[gangstajpimpin 10+ year member]

Ok. i got voltage from BOTH RCA's! It was alternating between .3-.7 on the DMM with volume at 30 out of 35. The only problem is that the RCA's dont receive voltage from the subwoofer output RCA's on the back of the Alpine 9887. I made sure that the subwoofer was on in the alpine headunit. Do you think the RCA output's are fried on the 9887 for the subwoofer channel?

I got voltage from the Front and Rear RCA's, but not the Subwoofer RCA. (switched RCA cable from subwoofer to rear)

Something is going on inside of the headunit as far as subwoofer output //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

When i tried leaving the RCA cable in the rear output and hooked it up to my subwoofer amp it didn't work...i was hoping it would //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif ...

Being semi-bassless ***** //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif...recommendations?

 

[mcsoul 10+ year member]

Ok. i got voltage from BOTH RCA's! It was alternating between .3-.7 on the DMM with volume at 30 out of 35. The only problem is that the RCA's dont receive voltage from the subwoofer output RCA's on the back of the Alpine 9887. I made sure that the subwoofer was on in the alpine headunit. Do you think the RCA output's are fried on the 9887 for the subwoofer channel?
I got voltage from the Front and Rear RCA's, but not the Subwoofer RCA. (switched RCA cable from subwoofer to rear)

Something is going on inside of the headunit as far as subwoofer output //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

When i tried leaving the RCA cable in the rear output and hooked it up to my subwoofer amp it didn't work...i was hoping it would //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif ...

Being semi-bassless ***** //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif...recommendations?

So you hooked the rear rca out to the mono sub amp and still no sound? That's

not good. Did you check your fader, it needs to be centered. Also make sure you do

not have a HP filter set at the HU on the rear output.

Get an mp3 player and a 3.5mm to dual rca male adapter and go directly to the

amp to see if you get sound. Wire the remote on to 12v. Did you check the fuses

on the amp?

 

[gangstajpimpin 10+ year member]

there is a single 80A fuse on the amp and it appears to be fine. I will check the amp sound later

 

[gangstajpimpin 10+ year member]

I hooked the 3.5mm to RCA plugs into the amplifiers.

As expected, the music played on the component amplifier but no sound came from the subwoofer amplifier //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif What could be going on?? should i just play a test tone or is my subwoofer fried? I tried to check continuity of the subwoofer but all the multimeter read was 1...sub is brand new and when i push down there is no sound made unless it is inside of the box (makes a squeaky sound)