dtorc4

WTF!!!!!

Not all of the time, but most, when I push my brake pedal in, my subwoofer amp goes into protection mode and cuts off. It will turn back on after a few seconds, even if I still have the brake pedal pushed in. My CD player keeps playing, and my midrange amp is unaffected.

Both amps are run off the same remote turn-on wire from the HU, and the power is distributed from a block behind my seat where the midrange amp is mounted. I checked my wiring and everything looks in order. I get 14.x volts from the alternator as well. I haven't popped any fuses for the car or the amps either.

One thing I noticed this evening is that my lights will dim for a split second when I apply the brakes, even with the stereo off. What could be the problem? I don't get a drop in voltage when I press the brakes. This is baffling me.

skateparkdave

Your gauge is likely lieing. Most larger car amps will shut off if there is not 12 volts constant or more available to power lead. The brake lights on C4's seem to draw alot of current. Even more so with the 3rd brake light to go along with the four others. I can notice my gauge going down when I sit at a long stop light. I'd say you may need larger gauge wire to your distribution block but if your lights dim when you hit the brakes with system off, then you either have a weak battery that doesnt hold power well with a load on it or a weakening alternator. Its also possible you have a loose ground somwhere.
Charge your battery for a good all nighter then see what it does. If your amp is big enough you may need a high output alternator and or a large power storage capacitor so your amps have the juice they need. You should'nt need it with just one amp but since you have several amps and a big system you may. Back in 86 I had an s10 blazer with a 5000 watt system that I competed in IASCA with. It had need of 4 batterys, a wall of caps and a second alternator. Not that you need all that, probably just a good battery charge and check under load, and maybe an alternator and ground check.

Mo_Bandy

Mo

XtremeVette

I don't think your problem is a case of having inadaquate wiring....(but while we are on this subject what guage are you running)

but anyways....I think you have either a break somewhere or bad ground...have you test the voltage when applying the brakes? I mean reproduce the problem while checking everything with a meter.....its got to be an electrical issue, so its got to pop up its head somewhere....Your amps turning off going to protection mode for a reason...they are designed to do this when they detect something that is incorrect in the electrical input they are receiving. So like I said, double and triple check wires, monitor voltage with a good multi-meter while reproducing the problem. (you may need 2 people to do this for obvious reasons of one person applying the brakes, while the other reads the meter and watches the amp for it to shut down into protection mode.

let me know how it goes....I have done plenty of systems and seen all sorts of odd things....just keep in mind electrical problems can be very intermittent and tempermental.....you have to monitor them very closely to find the actual problem....one little break in a wire (inside the sheathing, so you can't see the break) will produce frustrating troubleshooting.

One more thing to check into:
I can recall that I had 3 amps hooked up to my Alpine head unit and had similar shut down issues....for me....I put a relay on the remote turn on wire then routed the 3 amps off it...this solved my problem....apparently my head unit turn on lead could only handle 1 amp....the other 2 overloaded the head unit and caused it shut down....just a thought

jeff

SLOWRIDE

Had a Mercury Cougar had to open door for the radio to play(LOL). was inthe wiring

dtorc4

Oh yeah, I'm running 4 awg power to the block, then 8 awg power to each amp and 8 awg ground.

I've had this same system in the Vette for about 3 years now with no problems like this. This morning, the sub amp, and only the sub amp, cut off when I would activate the turn signals. I'm beginning to wonder if my alternator is going bad. The battery is only 4 months old. I can't seem to figure this booger out.

dtorc4

^^^

Could it be my alternator or the voltage regulator inside the alt going bad?

skateparkdave

Could be. Have you done the things suggested by myself and the others???

Bongtoke4jesus

This happened to me. I couldn't figure it out. Nobody else could. And then I figured it out. It's your ground wire. Sometimes you're ground wire just is not efficient enough. I have mine to the chassis underneath the car but I also have another one that is inside of the car. The one that was doing it was the one on the outside the ground. It was grounded. Really good but not as good as underneath my seats so I switched them and it quit.