1st gen 2004 double cab no sound from speakers suddenly

I installed a new(ish) HU years ago in my 2004 Tacoma Double Cab. Everything worked great. A few weeks ago I installed 4 new Infinity speakers and they were working perfectly up until a few days ago. I tried a CD, Radio, and BT... nothing worked. I removed the HU and doubled checked my connections and they were good. I checked the continuity using a multimeter on the speakers and they were fine. I reinstalled and still nothing. I removed the HU and cut the front passenger side speaker wires and ran them direct from the HU to a speaker I had laying around and I was able to get sound from it. I saw in the tundra forums that 1st gen Tundras had a factory amplifier installed, sometimes tucked away in the dash. Does the 2004 Tacoma have one too? Something is causing an issue between the speaker and the HU and I am not sure what it is. Any advice?

I attached a picture of two things tucked behind the dash. I have no idea what they are (computers maybe?), but I figured it wouldn't hurt to show them just in case one is an amp or something like that.

 

Installs new speakers - they quit working shortly after. I'd be looking in that direction. Losing all 4 then having a random speaker work is odd. What's the nominal impedance at the head unit? If you went lower than the head unit is rated, you could be temporarily be putting the amp in the head unit in protect.

No, these don't have factory amps.

 

The random speaker was not one of the ones that I had installed. It was just a regular speaker I had hanging around. I might try connecting the HU directly to one of the speakers to see what happens. Just not in the mood to take the door apart this evening. I see now that the speakers are 3Ω which seems odd to me. I guess I am used to them being 1, 2, 4, 8... Not sure what I need to do or if I can do anything.

AVH-P3400BH
Use speakers over 50W and between 4Ω & 8Ω (impedance)
https://www.pioneerelectronics.com/StaticFiles/Manuals/Car/AVH-P4400BH_OwnersManual051712.pdf

Infinity Reference REF-8632CFX
https://www.infinityspeakers.com/speakers/REFERENCE+8632CFX.html

 

Right - we're on the same page with a random speaker. 3 ohms doesn't seem like it'd be enough to shut down the amp, but maybe? Maybe that number's not right? You need to measure impedance at the head unit to see what it's seeing. You'd wanna pull the HU and see what you're reading at the harness.

Then again, if the random speaker played and the others didn't and were all connected, there's another curiosity as you probably aren't working with discrete channels. I'd think if the amp were going into protect, it would cut all channels.

 

I have a feeling you are right... unfortunately.

 

I would check all of the speaker wires at the head unity for continuity to ground. If a wire is grounded, that’s your problem. I used to see it pretty frequently. Maybe just pull the door panels and inspect all the speakers anyway