Amp location

Installed all mew speakers and worked with factory radio. Installed aftermarket radio all speakers continued to work for about 3 months, then they all quit playing at same time. Installed 3 Hu speakers don't play a sound. Truck has amp fuse but amp is not under passenger front seat. Speakers still work when directly connected to Hu but do not through truck harness. Any help would be appreciated.

 

Is it a JBL system? There should be an amp under the seat if it is. Non-JBL doesn't have an amp.

 

It isn't a jbl system. If there isn't an amp. Why is there a 30 amp fuse in the amp slot under the hood with power before and after. And all speakers stopped at same time so wiring harness failure?

 

My 2013 had that fuse as well but no amp. What is your full system setup and how is it wired? Do the speakers go through any type of signal processor, line out converter, etc? On a factory setup for the 14-21, the dash speakers run directly from the head unit, and the door speakers run through a small amp. My 2020 SR5 has a factory amp but its not a JBL system. Confusing isn't it? There is absolutely nothing under the seat at all?

 

Radio wired to stock harness with plug and play. Dash speakers wired in with front door speakers. There is absolutely nothing under the seat.

 

Just trying to figure this out before I break down and run all new speaker wires

 

If all speakers work when connected directly to the high-level outputs of the A/M head unit it certainly is acting like there is an amplifier somewhere in the mix. I am new to this platform but certainly not to car audio. It's been a hot minute since I've torn into one of these trucks, but intuition is telling me there is absolutely something between radio signal out to the factory harness and output from the speakers.
Do you have a picture of the radio harness where it is connected to the harness for your head unit?
Have you investigated the area below the radio behind the HVAC controls for any silver box that has heat-sink fins on it? The only other area that i remember (again it's been a fortnight) was behind a panel behind the rear seat on the back wall of the truck, but that could possibly be incorrect.