if you mixed up ground and power at the amp terminals it would spark, blow the amp fuses, and/or damage the amp.

let me clarify some steps. A digitial multi-meter (DMM) is required for any troubleshooting. So you can either take your car to a shop and pay them, or spend a few bucks and buy an invaluable tool... or borrow one. Note that you should learn how to safely use the DMM, there are plenty of online tutorials.

#1 - check fuse at the battery for amp power wire and any amp fuses. Always a good first step. If you have AGU (cylindrical) fuses you may not be able to just look at them, a DMM (digital multi-meter) will allow you to measure voltage at the amp terminals which also checks fuses and wire continuity.

#2 - Disconnect all wiring from the amp except power, ground, and remote. (i.e. RCA's and speaker wires should be disconnected)

with your DMM, measure voltage at the amp power (+) terminal. do this two ways. first, place the red DMM lead on the amp (+) terminal and the black DMM lead on the amp (-) terminal. second, keep the red DMM lead on the amp (+) terminal but move the black DMM lead to a ground screw or even direct to the battery ground.

You are looking for a difference in voltage reading relative to two different grounds. This can help troubleshoot your amp ground. With the car off you should measure no less than 12VDC. with the car on you should measure around 13.5-14VDC. If you measure less than 10VDC then you have a bad ground, blown fuse, or mixed up wiring.

Recognize that DC current "flows" from negative to positive. Long story short, the initial naming convention was backwards and no one wanted to change it. As such, grounds are crucial for a properly functioning system.

ALWAYS DISCONNECT BATTERY NEGATIVE WHEN CHANGING AMP GROUNDS

if you cannot get your amp power light to illuminate green when >12VDC is measured at the amps (+) terminal and remote turn-on terminals relative to amp (-) terminal, you have a bad amp. At this point I would remove the amp and bench test it with a separate power supply.

#4 - if you are able to get the amp to illuminate green, fuses are good, grounds are good, remote turn-on is good, etc. then it's time to measure speaker wires.

With your DMM set to Ohms, you can touch the DMM leads to the speaker wire pairs (not connected to the amp). The reading you get will depend on the subs you have and how they are wired, see below. if you get less than 0.5ohm you have a short.

You need to provide us with the Mfr/model of the amp and the mfr/model of the subs - including voice coil impedance (dual 4, dual 2, single 4, etc.). Also, tell us how you wired the subs voice coils (parallel, series, etc.). If you don't know the impedance of the subs, it's printed on the magnet.

#5 - after you have verified you do not have a short in your speaker wires, and that they are properly wired for a final impedance load that is within the amplifier recommendations, you can connect them to the amp.

ALWAYS TURN OFF AMP WHEN CONNECTING SPEAKER WIRES. you can do this by shutting off the head unit.

 

Initially, I addressed the speaker wiring impedance, but indirectly. if you wired the subs for an impedance that is lower than the amp can handle, it can instantly go into protect. However, it should go out of protect after you remove the speaker wires (hence my i suggestion to remove them).

Note that you may need to shut the amp off, then turn it on, for it to go out of protect. Always turn the amp off when making wiring adjustments.


AGU fuses utilize a soldered fuse element inside. All other fuse types have a continuous metal - ATO, Maxi, Mini, Midi, AFS, ANL, etc. As such, AGU fuses are unreliable as they can fail from heat. You can test AGU fuses by using your DMM to measure voltage on both sides of the fuse (also handy method for testing ATO fuses in your fuse box), or you can test an AGU fuse with a DMM measuring resistance.

if you can take a pic of the other side of the amp, showing wiring connections, that would also be helpful.

Cheers!

 

I think i found my problem. I'm not sure if i cause it or not. I noticed that one of the fuses,the one that lights up, that one didn't come out of the amp. The other one the cap came off, and i didn't know if that was bad or not. So, i took appliers and pulled the pieces out. I noticed that the metal in the middle was broken apart. So I'm guessing it's the problem

I'm just not sure if i did that. Do you think having 2 wires to one ground might cause that? I had a capacitor and the amp wire at one bolt =\ which i wasn't too sure about but i was somewhat in a hurry. (my bad) Or it may have been the 9 gauge wiring for the capacitor and 4 gauge for the amp? maybe a difference in voltage?

Oh and do you think that that fuse being blown out would cause the amp to go into "protect?"

Thanks

 

i didn't see that your fuse holder had LED's. in that case, the LED can be an indication of a blown fuse. so your amp fuse was fine but your cap fuse was blown?

i didn't notice you had a capacitor. you can ground the cap and amp at the same place.

the cap should have the same size wire as the amp, or just remove it.

don't fuse the cap, wire it directly to the amp terminals, as short as possible, but with 9awg wire it's not doing anything anyway.

pull the cap until everything else is functioning perfectly. then reconnect it directly to the amp power and ground terminals.

i'm not sure any of this would cause an amp to go into protect. that is typically an isolated indication of problem at the speaker terminals. we still need the sub and amp model numbers to help verify you don't have an impedance issue.

 

Okay i went out and bought a new fuse. The amp now works and the light is in green.

My amp had a blown fuse,(fuse lit red) so i switched that out. The cap i just disconnected because we felt not having the matching wires wasn't a good idea.

Oh alright i wasn't sure i could ground it in the same place or not. And i thought you wanted the wires to match the size? I'll take a pic of the capacitor and show you how i was gonna hook it up. Basically, ground wire and then the power to the capacitor and from there to the amp. Is that an alright hook up?

Yes i did take of the capacitor for now. But i can tell my lights dim when it hits the lows.

My next question is how i control my sub level with my head unit. Because it says i have sub preouts along with sbwfer control. I'm not seeing it as an option on my head unit? Is that bad RCA's or just the amp is too old?

The amp is a power acoustiks ps2-1800

I am not sure how to find the models on the subs. I probably have to take them out and i'm not sure if i wanna go in there yet.

 

good call, i mistook the red light as a protect light and not a fuse light.

 

wire the cap as described below. you can wire power and ground directly to the amp, some amps come with connections built into the amp for a cap.

Use 4awg wire for a cap smaller than 2 Farads.

What head unit do you have? Some require that you manually turn on the subwoofer option in a menu. Then it adds a sub level control option along with balance, fader, etc.

 

So, should the power wire coming from the battery go from the cap to the amp. or from the amp to the cap?

I have a Kenwood KDC-MP242

It says it has a sub-wf level control. Along with low pass filter.

 

http://a248.e.akamai.net/pix.crutchf...3/113MP142.PDF
refer to page 9 of your owner's manual for turning the sub pre on. be sure to utilize the other features of the head unit such as crossovers.

cap wiring depends on the amp and layout.
power wire to cap and from cap to amp can work fine. use ring terminals at the cap (of course).

 

Okay thanks. i now have the setting for the sub on my head unit. My question now is which low pass to choose. 80 120..or?

But that's not really even my main concern now. My amp and subs will work for like 5 minutes now, and then the fuse goes out. I've checked all the wires and they all seem good. So i don't know if i need better quality power wire or to make a new ground.

The type of subs i have are KFC-w3011.