1976 El Camino... no sound. What gives?

[Stingroo 10+ year member]

So I got this El Camino. It had an ancient Sony head unit in it, and two equally-ancient 6.5 speakers in the doors. I planned on putting the head unit from my other vehicle in it. Here's where the fun starts.

The installer hacked all the wires in the dash to crap. Not cool.

So I grabbed the multimeter, found a constant 12V source, a ground, and a 12V hot. Cool. Wired up the radio. It turns on. Excellent.

Ran to the store, got new RCA cables, an inline fuse, and some speaker wire. I already had a lot of spare 4 AWG wire sitting around - this isn't going to be a big system. Just a 4ch amp to run the speakers. Ran wires to the each of the speakers, connected them to the amp, connected main power wire w/fuse to battery positive, ran to amp, connected remote wire and spliced in to the radio harness.

Moment of truth, turn the key on. Amp lights up, radio lights up, switch it to tuner... nothing. Switch it to USB... nothing. No sound from speakers. At all. This radio was working just fine 2 days ago in my wrecked car when I pulled it.

If I take the speaker wire and connect it to the radio harness itself, it works just fine.

So I use another known-good amplifier (as in... it was in the car that took me to the store just 30 minutes prior), and still, nothing.

Could the RCAs on my head unit be bad? If so, how do I test?

Other suggestions?

I'm at a loss.

Click to read more...

 

[Side Show 10+ year member]

try another set of rca's on that unit..... also check the deck settings... might be something on there

 

[Side Show 10+ year member]

amp might be bugger'd? (no output) or deck rca's pre-outs might be bugger'd( no output) or rca's might but cut/broken/damaged (or even just turned off on the headunit) also try reset the headunit, might work too..... make sure the rca's on the deck are an output and not an aux input.

 

[Stingroo 10+ year member]

Deck RCAs are all output. It's a Pioneer DEH-P8400BH. I just bought the RCAs today, I'm not thinking they're the issue. I'll try resetting the unit though.

Amp was known good prior to install. It's probably something terribly obvious I'm missing.

 

[Side Show 10+ year member]

did you use front rear or sub output from the deck? I'd say reseting the deck will work... check your rca inputs on the amp and make sure they are in the input and not the output section, what amp?

 

[Side Show 10+ year member]

make sure the headunit isn't faded all the way to the rear ect

 

[Stingroo 10+ year member]

Amp is an Alpine MRP-F300.

 

[robert420 10+ year member]

how do you have it wired exactly???

 

[CrossoverOre 10+ year member]

try run the amp high level and see what you get. If you have a mini amped speaker you can use that to test rca signal. Could also use a dmm and see if you have voltage through the line.

 

[Stingroo 10+ year member]

how do you have it wired exactly???

Head unit is wired and turns on.

RCAs from head unit to amp input.

Remote wire on head unit harness to amp.

4 AWG from amp to battery w/80 amp inline fuse

4 AWG to ground.

Two speakers on channel 1 and 2 of amp. Soon, I'll be adding another pair of rear speakers for ch. 3 and 4, but it needs to play first.

If I wire the speakers directly to the head unit, they play.

But... that kind of defeats the purpose here.

 

[jrdnhsnbrg 10+ year member]

Head unit is wired and turns on.
RCAs from head unit to amp input.

Remote wire on head unit harness to amp.

4 AWG from amp to battery w/80 amp inline fuse

4 AWG to ground.

Two speakers on channel 1 and 2 of amp. Soon, I'll be adding another pair of rear speakers for ch. 3 and 4, but it needs to play first.

If I wire the speakers directly to the head unit, they play.

But... that kind of defeats the purpose here.

Is the amp turning on?

 

---------- Post added at 02:29 PM ---------- Previous post was at 02:28 PM ----------

 

Fuses good? Remote wire good? Ground and power connections are good?

 

[FamousMassacre 10+ year member]

Did you turn the volume up?

 

[Stingroo 10+ year member]

Amp turns on. Wire is all brand new.

Har har har, yes I turned the volume up. You so clever.

 

[jrdnhsnbrg 10+ year member]

Amp turns on. Wire is all brand new.
Har har har, yes I turned the volume up. You so clever.

Set the gains on the amp?

 

[CrossoverOre 10+ year member]

you need to verify the rca in deed has voltage. Do you still have the high level input plug for the amp? if you do just connect left front output from deck to high level input harness and see if you get sound. Really sounds like your deck rca outputs are toast.