MTX Thunder 8302 Car Audio Amplifier Logo
scott lowes Posted on Sep 29, 2006
Answered by a Fixya Expert

Trustworthy Expert Solutions

At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.

View Our Top Experts

Subs going off the hook

My subs worked fine... then they just started to thumop without any music going to the amp. any ideas??

  • Anonymous Mar 18, 2008

    I've had the same problem with this amp thumping without music, but with power on, except mine stopped working all together shortly after. Has power running to it, grounded fine, but the power light won't even come on now.

  • Anonymous Apr 10, 2008

    my amp was working fine for a while. then one day i started my car and the amp just went haywire making a thumping noise. as it was doing it i unhooked my rca cables from the amp so there wasnt any sound going into the amp and that didnt do anything. any ideas as if the amp is shot or if it something simple in the wireing.

×

6 Answers

Mark Skinner

Level 2:

An expert who has achieved level 2 by getting 100 points

MVP:

An expert that got 5 achievements.

Novelist:

An expert who has written 50 answers of more than 400 characters.

Governor:

An expert whose answer got voted for 20 times.

  • Expert 79 Answers
  • Posted on Feb 10, 2013
Mark Skinner
Expert
Level 2:

An expert who has achieved level 2 by getting 100 points

MVP:

An expert that got 5 achievements.

Novelist:

An expert who has written 50 answers of more than 400 characters.

Governor:

An expert whose answer got voted for 20 times.

Joined: Oct 20, 2008
Answers
79
Questions
6
Helped
31402
Points
150

Most of the time this is caused due to your RCA's from your head unit. Either your head unit itself had a bad ground or another problem causing this. You can try taking a piece of wire and touch the outside of the RCA's ground point and touch the other end of the wire to the bare metal of the amp or to the power ground and see if it quits. Also unplug the RCA's and see if the thumping stops. Then you know it's the RCA's. If it does'nt stop make sure your amp is properly grounded. Try and remember if you had any problems before the thumping like the music cutting in and out, lights dimming or anything. The amp worked fine before so if it started doing this out of the blue than it's the head unit or amp. Once you rule out the RCA's, (head unit) then move on to the amp and as I said check the amps ground. If thats fine then it's your amp internaly having a problem. I've repaired numerous amps with this problem. Each amp can and will have different reasond why this happens and some have the same problem. It could be in the power supply section or in the output section of the amp. Sometimes it's the bias resistors in the amp. You don't know til you start checking. If you ever need help, I own a small business called Mark's Car Audio & Amp Repair, 727-247-5779 hours Mon-Fri (9am-6pm) Sat (10:30am-3:30pm) I have over 20 years experience and I'm the cheapest amp repair or any electronics repair in the USA. I also help people over the phone or through video chat or just chat using Skype to walk them through testing an amp out for the problems. It helps if you have some knowledge of electronics but if you don't it's fine. I'm currently working on a DVD teaching car amplifire repair made easy. It's for people who don't know anything about electronics. Also there's a section for that shows you how to just jump right in and start diagnosing an amp without learning some basic electronics first, which is in the first section of my DVD. I find allot of people who just want to jump right in. I teach this part in a way that is safe and understanding just as I do when I help a person through video chat. I am very busy with helping and repairing so if you contact me by phone and I don't answer please leave a name and number so I can return your call.I usually answer but I might be in the middle of something where it would be hard for me to stop. Thank you and have a nice day.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/mark_b53a7494531bf96d

Anonymous

Level 1:

An expert who has achieved level 1.

  • Contributor 1 Answer
  • Posted on Nov 18, 2007
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

Joined: Nov 18, 2007
Answers
1
Questions
0
Helped
235
Points
1

RCA IN BACK OF RADIO IS BAD I had same problem try a other radio that fix mine

A

Anonymous

I just fixed this same problem...it was a bad rca cable..when i pulled out the head unit and banged the two rca's together they made the subs hit. I thought it was my amp dyin, cuz i had good ground and figured the 6 years finally put its toll on the amp. I realized when i was rocking out and hitting my steering wheel that my subs hit when i banged my wheel and dash. Nick

Mike Ryan

Level 2:

An expert who has achieved level 2 by getting 100 points

MVP:

An expert that got 5 achievements.

Governor:

An expert whose answer got voted for 20 times.

Scholar:

An expert who has written 20 answers of more than 400 characters.

  • Expert 98 Answers
  • Posted on Nov 27, 2006
Mike Ryan
Expert
Level 2:

An expert who has achieved level 2 by getting 100 points

MVP:

An expert that got 5 achievements.

Governor:

An expert whose answer got voted for 20 times.

Scholar:

An expert who has written 20 answers of more than 400 characters.

Joined: Oct 21, 2006
Answers
98
Questions
6
Helped
110860
Points
160

I agree... make sure your amp has a good heavy gauge wire for the ground(and power for that matter),make sure the ground wire connection to the body from the amp is clean(bare metal, no paint or rust) and tight ,and make sure your battery-to-body ground under the hood is good too. If you are not sure take a piece of 8 or 4 gauge wire and make a new ground directly form the negative terminal of the battery to the chassis of the car. this will ensire your grounded well...

Anonymous

Level 1:

An expert who has achieved level 1.

  • Contributor 1 Answer
  • Posted on Oct 13, 2006
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

Joined: Oct 13, 2006
Answers
1
Questions
0
Helped
235
Points
0

I will agree with the first solution posted but you can also start checking values with an ohm/volt meter, a digimeter, I would start by checking values of the MOSFET Transistors, If you get more than a couple of bad reading then you got more of a problem than its worth to try to repair it unless you know your stuff in this field, but if you only got like one bad valued transistor you can isolate this circuit and see what happened to make this transistor fry like bacon then replace those parts as well I will give it an 80% chance that you need new amp but what do you have to lose, it doesnt work anyways :0)

Anonymous

Level 1:

An expert who has achieved level 1.

Corporal:

An expert that has over 10 points.

Mayor:

An expert whose answer got voted for 2 times.

Problem Solver:

An expert who has answered 5 questions.

  • Contributor 18 Answers
  • Posted on Oct 04, 2006
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

Corporal:

An expert that has over 10 points.

Mayor:

An expert whose answer got voted for 2 times.

Problem Solver:

An expert who has answered 5 questions.

Joined: Oct 04, 2006
Answers
18
Questions
0
Helped
25896
Points
25

Your ground is the problem here, try moving your ground to a different spot or try double grounds

3 Related Answers

Anonymous

  • 5 Answers
  • Posted on Aug 10, 2009

SOURCE: mtx jh600 feed back in subs light on amp the bolt is blinking

check that the ground wire is bolted tightly to the chassis of the vehicle.

Anonymous

  • 36 Answers
  • Posted on Sep 21, 2009

SOURCE: mtx 1000xd led light is flashing and the subs will not work

The light flashing usually means there is a short somewhere. Check your wires to make sure there are no slices and are touching. Also check to make sure you have your remote wire hooked up.

Anonymous

  • 13 Answers
  • Posted on Sep 08, 2011

SOURCE: My 1501d is making a wierd noise when i turn it on almost like an amplifed line noise but thats not the problem??

I had the same problem. Its your rca inputs. They need to be resoldered.

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
1answer

What's the best way to hook up 2 Hifonics hdl12d4 subwoofers to a mono amp

Ok, your post has two different models listed. Let's start with something you need to know about your amplifier. Is it one ohm or two ohm stable. This will make a difference. Also, whether your subs are single voicecoil (HFI12s4) or dual voice coil (HDI12d4).

Let's start with the easy scenario. Let's say your amp is two ohm stable and you have two single voice coil subs. It's simple. You go from the positive of the amp to the positive of both subs and the negative of the amp to the negative of both subs. This will provide a 2 ohm load to the amplifier, thus pulling all the power out of it.

Unfortunatley, if you have two dual voice coil subs, you won't be as efficient. You will only have the options of a 4 ohm load or a 1 ohm load.

This is where having a one ohm stable amp would come in handy. If the amp is one ohm stable, hook the positive of the amp to all 4 of the positives on the subs, and hook the negative of the amp to all 4 negatives of the subs. This produces a 1 ohm load.

WARNING!! If you have a 2 ohm stable amp DO NOT use the last wiring scenario. It will fry your amp.

Now, the last is a little trickier. This is for two dual 4 ohm subs. Follow closely. Hook the positive of the amp to one of the positives of each sub. (do the next step to both subs) Go from the negative of the voice coil that you hooked positive from the amp is hooked to, and hook that to the positive of the unused voice coil. Then go from the negative of that voice coil and hook to the negative of the amp. Make sure this is done on both subs. This will give you a 4 ohm load.

Hope this helps
0helpful
1answer

My amps and subs are working, but my subs aren't hitting.

Try bypassing the remote wire staight to power instead of the stereo
0helpful
1answer

I have a few problems. i have 2 amps and 4 subs. first problem is when i connect one amp to my speakers it just hisses and crackles. this never happened before. when i turn up the gain to try and get...

The first amp, sounds like there is straight power going through the gain instead of it being limited. The second amp...hook the other subs up to it and see if it sounds ok. If so, then the subs are messed up. If it sounds the same, make sure the subs are connected correctly.
0helpful
1answer

Amp wire pushin to much base out of car speakers and not to subs

Umm.. subs are usually meant for bass. do you mean amp power wire? if you just want to be able to hear the mid's and highs better just turn the bass down either on the equalizer on your amp or on your cd player.

0helpful
1answer

Subs will not work right.

the subs coils are melted and shorting out so the amp shuts off
0helpful
1answer

Just installed my cva-1004 in my truck and all connections are good get dvd picture but no sound do i have to have the remote to select inputs i also hooked amp and subs up amp to the sub rc's at the back...

Hey Ryan I have the same thing dude has and my sound only works when I have my subs are hooked up. Without my subs hooked up I have no sound at all. Do you know how I can fix this?
0helpful
1answer

Car amp has power but will not push subs

output blown on power supply - repair by tech required.
0helpful
1answer

I do not hear any music through my 10" M Audio Subs (M Audio Sound System)

If you know how to use a multimeter, you can test the amp this way:

-unhook the subs
-hook up a cheapie speaker you know for sure works to one of the channels
-unhook the audio inputs
-turn the amp on
-set your meter to VDC
-put the positive probe on the inside of the input connector, being sure you make contact with th inner contact
-take the negative probe and tap it on the outside of the connector

What you are doing is sending a low voltage (replicating an audio signal) into the amp audio circuit and allowing the amp to amplify it. If the amp makes the speaker pop each time you strike the probe, the amp is working.

You mentioned you need a 4 channel amplifier make the two, dual voice coil subs operate. The is not true and by hooking them up like that, there's a chance of damaging the subs. The reason is that the dual voice coils are interwoven and they have to get electrically identical signals or they fight against each other. The can mechanically fail, then, electrically fail, then even damage the amp too.
Not finding what you are looking for?

245 views

Ask a Question

Usually answered in minutes!

Top MTX Car Audio & Video Experts

Jose Ramirez

Level 2 Expert

264 Answers

Marvin
Marvin

Level 3 Expert

85242 Answers

ZJ Limited
ZJ Limited

Level 3 Expert

17989 Answers

Are you a MTX Car Audio and Video Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...