Tricky Amp Issue

[Luminous311]

Hey guys, I've got an interesting issue with my amp, or something peripheral to the amp. I'm not sure what it could be.

It started when my amp cut out entirely. After a few months of successful operation, no lights would illuminate. I tested power voltages (~12v), remote wire voltages (~12v), all cables were continuous, and the ground was grounding. The head unit was sending a signal through the RCA cables, though that shouldn't matter to the power on, as far as I know.

It was a crappy, hand-me-down Sony Xplod amp, so I figured it went as the name suggests it will, and I ordered a new one.

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The new amp arrived yesterday, and I encountered the same issues. No illumination. I went through the same process again, and saw no results. I played around with sending the power voltage through the remote wire, which led the amp's blue track lighting to illuminate briefly, though that dimmed out quickly, and no power lights ever came on. This track lighting test can be repeated time and again, though I didn't know what to make of it. I have a hard time believing this new amp is DOA, especially given that it produces the same results as the previous one.

So, where is all my electricity going?!?!

I couldn't find anywhere on here where someone had the same issue, so I thought I'd start a post. If I'm being stupid, please let me know. Thanks for your help, guys!

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[Kangaroux 5,000+ posts]

if you can i would return that amp, they are complete junk. are you sure nothing is being shorted, even just a little?

 

[Robert 2001 10+ year member]

Try redoing your ground even though you have continuity does not mean its a good ground. Aweak ground can cause power up and voltage issues on any size amp

 

[Luminous311]

Kangaroux, I didn't get a Sony Xplode this time around. I only got it the first time because it came very cheap with a wiring kit I bought from a friend.

Robert, I'll give that a go. I'm just wondering why it'd all of a sudden cause a problem, where there was none before. I'll report back in a bit with my findings.

 

[Robert 2001 10+ year member]

Vibrations can do crazy things. Ive had wires vibrare loose sunvisors and mirrors fall off from bass so it can loosen a screw up even more so in smaller cars and suvs.

 

[Luminous311]

The ground connection seemed pretty tight when I went to look at it. There's no corrosion at the location or anything indicating wear or loosening. For all intents and purposes, it should work as it always has. It was very properly crimped and installed, if I do say so myself //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Also, I just noticed there was more to your post, Kangaroux. There may be a short, if only just a little one, somewhere in the line. It'll take a while to dig up the cabling and give it a good inspection, and I can't do that very well tonight. Intuition and a multimeter seems to tell me that there aren't any shorts, but there'll be no certainty until I check.

It's possible the head unit is a pile of crap. I've got a spare one of those I can use to check it against, so after making sure everything is continuous, I'll look into the head unit situation.

Thanks for all your input so far, guys. I'll give it its due diligence and let you know how it's looking tomorrow.

 

[keep_hope_alive Premium Member]

disconnect speaker wiring, then power up the system. a short in the speaker wires would cause the amp to protect itself. some amps have protect lights, some do not. if the amp lights up, you know your speaker wires are too blame, and your search can start there. a DMM measuring resistance on the wires (and from each wire to ground) can help you track the problem. often, a wire will come loose on the speaker/sub and short out.

good job testing voltage, that is always step one. sometimes, you can have voltage but not enough contact to actually let it power on (like when your dome light is on but the car won't start and it's because the battery cable is just loose). that is why we recommend redoing the ground, usually one of the first steps when you have voltage.

you can test your ground continuity by using a DMM to measure resistance from the amp ground terminal to a metal point elsewhere on the car. less than 0.5 ohms is good. more than 1 ohm is bad (depending on the quality and accuracy of the meter). ensure you have bare metal, not paint, at the grounding location (and tell us/show us where you grounded the amp). what size power and ground wires?

verify the fuses on the amp itself are not blown (if the amp has fuses). do this with a DMM by measuring voltage on the small metal tabs on the fuse (with fuses inserted). if you have voltage on one side of a fuse but not the other, the fuse is bad. that's the only way to know for sure (visual inspection can be misleading at times).

 

[grandam888 10+ year member]

i would check ground, you may have chosen a bad grounding point. move your ground, check battery power wire connection, and power the amp up with NOTHING but remote, ground, and batt + connected

 

[Luminous311]

Well, I checked the ground, which was good, so I tore out all the wiring and I took a multimeter to everything. And now I have my foot in my mouth.

It turned out that I had a bad in-line fuse, which looked alright to visual inspection, and I swear it conducted when it was connected to the battery. When I tested it individually, though, it didn't conduct.

So that was that Thanks, guys, for all the help, and now I definitely know I have good power in the car.

 

[GAMEOVERCCA 10+ year member]

yea fuses should always be the first thing you check lol surprised no one said that...