Can you test for power

[JAL232 10+ year member]

from your amplifier speaker terminals. I just installed my new amp on my subs (amp blew) and the amp has power, green light on, hooked speakers up but have nothing from speakers. So i dont know if they are getting power from amp or what

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[tRidiot 10+ year member]

Use a multimeter. Set it to AC voltage and put it on the output terminals of the amp.

You can also use the ohms setting to check the impedance of your speakers. And the DC setting to check power at the amp's terminals, although if it's lighting up, sounds like you've got input power.

You checked your RCAs? You can also check voltage there for signal....

 

[JAL232 10+ year member]

what do you set it at to check power from rca's...I for some reason think this is the problem..Cause what else could it be...Subs played great right before amp went POP....then its been like 2 months before i got a new amp from HIfonics, nothing changed, but now no playee playee

 

[tRidiot 10+ year member]

You check output voltage at the RCAs... use the AC voltage setting, also.

Never checked this one myself, but if you need me to (if someone can't back this up), I can go check it on my car to be sure. Place the leads of the multimeter on the "pin" in the center of one RCA jack, and the other on the outer "ring". Doesn't matter how much voltage you're getting, if you get anything then it shows some voltage coming down the pipe.

Another alternative is to use an mp3 player of some sort with an RCA adapter (i.e., headphone jack-to-RCA adapter) and plug it directly into the inputs on your sub amp. If you get music out of your speakers, then the RCAs came unplugged somewhere along the line, or you're headunits RCA outputs shorted, perhaps.

 

[JAL232 10+ year member]

Thats a good idea..There is a black and red rca, so ill just ust meter and set to AC and hope to get something from HU....if they shorted there...then what..bad HU...I dont see how they would have though

If a sperker wire came loose in sub box from sub, would this cause both to not play? I dont believe so

 

[jdawg 5,000+ posts]

you can ohm the wires coming out of your speaker box

 

[johnson 10+ year member]

If a sperker wire came loose in sub box from sub, would this cause both to not play? I dont believe so

If they were wired together and someone came loose, it would not play.

 

[tRidiot 10+ year member]

Ok...

You can do the AC voltage test on either RCA, doesn't matter.

If you check the impedance of your speakers (aka "ohm the wires" lol) it will tell you a couple of things:

1. Is the circuit still complete?

2. If speakers are wired in series, has one or the other fried the VC?

3. If speakers are wired in parallel, perhaps which speaker has fried the VC?

Yes, there may be an issue with inside-the-box wiring. It amazes me how many people don't realize how useful a multimeter can be when troubleshooting electronics. They're like $3.99!

Let us know what you find.

 

[Flipx99 5,000+ posts]

Keep in mind many DMM have a fuse..it will still somewhat work if it is blown, but the reading won't be correct.

 

[johnson 10+ year member]

It amazes me how many people don't realize how useful a multimeter can be when troubleshooting electronics. They're like $3.99!

Refer to this thread.

http://www.caraudio.com/forum/showthread.php?t=266049

I'm sorry is that a volt meter for a battery? What would that do? I already know the battery works..

 

[JAL232 10+ year member]

To "ohm my wires" I simply turn power on, then put multimeter terminlas where? Box terminals? or where? I have a multimeter just never used it..haha

 

[tRidiot 10+ year member]

Indeed....

I don't even bother changing the batteries on my DMM.... I just toss it and buy a new one. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[tRidiot 10+ year member]

To "ohm my wires" I simply turn power on, then put multimeter terminlas where? Box terminals? or where? I have a multimeter just never used it..haha

To "ohm your wires", lol, aka check the impedance....

Leave your system OFF.

1. Disconnect speaker leads from the amp

2. Set DMM to ohms (prolly the 20 setting on most DMMs)

3. Place the positive lead on the postive speaker wire, neg on neg. If you get a reading in the range of what your sub's impedance ("ohms") should be, then it's prolly ok. For example, a sub with dual 4-ohm coils might have each coil read from 3.2-3.6 ohms... or when pre-wired inside the box, checking the leads coming out of the box could read ~1-1.5 ohms (if wired in parallel) or 6.5-8 ohms (if wired in series).

If it gives you some really high reading, then the coils are likely fried> with no reading, you can check continuity of the circuit (some meters have this setting) which will tell you perhaps one speaker wire is off, or maybe the coil is shot.

 

[tRidiot 10+ year member]

It would help if you gave us more info.

How many coils per speaker?

What impedance per coil?

How are they wired? All coils in parallel? Series/parallel?

Speaker leads coming out of the box for each speaker? Wired inside the box with one set of leads exiting? etc.

 

[johnson 10+ year member]

I believe the TC DB500's were single 4 ohm.