MTX thunder 304 4ch red amp light comes on but no audio have triple checked all connections and they seem alright

Check fuse on amp under hood. Also, check wire connections makes none of them are loose and move your RCA jacks around to see if you have a short.

If you have proof of purchase(invoice or receipt) showing the purchase date and you are still within the warranty period then yes it would be repaired by MTX under the warranty guidlines, and by the way MTX is great at customer service and they are great to work with(very fair)!!!!
Keep in mind that the seal on the bottom of the amp cannot be broken or that will void warranty coverage.
Give them a call, you will be glad you did!
800 225 5689 - MTX Customer Service & Amplifier Service Center
Good luck !

first of all you should check the minimal impedance your amp handles , if is class d it should handle between 1-2 ohms total impedance in a mono conection , meaning whatever quantity of subs you have hooked to your amplifier,their total impedance should the minimum the amp handles that way all the power from your amplifier will be used.

the amp is under to much pressure get a bigger 1

Could be a blown speaker/sub or a wire is crossed in the sub enclosure.

Hello tonytone54, The ground should go directly to the vehicle frame, never through a cap, fuse, or anything else. Also, if you are connecting positive through a cap, make sure that you charge the cap before connecting it. Hope this helps.

Even if there is no visible damage, it could be that one of the transistors is blown, Use a multimeter to check the resistance of the transistors.

maybe the audio amplifiers Ic´s damaged or the power fet

You need to contact MTX tech support before the warranty runs out. You'll probably have to get an RA number to send it back.

 

http://www.mtx.com/caraudio/contactMTX.cfm

 

 

If there is a zero ohm connection across the B+ and ground terminals, it should blow the fuse as soon as you apply power.