Mazda 6 Forums banner

1 - 20 of 28 Posts

·
Registered
Joined
·
75 Posts
Discussion Starter #1
Where would be the best entry point from the engine bay (battery) in to the interior.
I'm needing to run thick power cble for two amps.

Any help would be great.

Thanx guys:) :)
 

·
Registered
Joined
·
37 Posts
Reading Topic: ? amp wiring

Hi

You can try the MAIN Cable wich is connected on the Inboard Fuse-BOX - but be aware it´s no the best solution !

I assume to connect directly to the Main-Fuse-Box at the engine-Room there you see a 100/120A Fuse - try this Point.
 

·
Premium Member
Joined
·
2,898 Posts
Reading Topic: ? amp wiring

Why does he need to connect to the fuse box to hook up an amp? Hes simply looking for the best spot to pull the power wire through the firewall without having to drill any holes. As far as fuses go.. you should have a fuse holder with atleast a 60 AMP fuse somewhere near where it connects to the battery.

Unfortunately I havent had the luxury of being able to investigate this. But it seems as though some of the other posters here, namely diesel, is getting a full system install and might be able to get a pic of where the best place might be.
 

·
Registered
Joined
·
657 Posts
Reading Topic: ? amp wiring

You'll have to drill through the firewall, trust me. My installer couldn't even find a hole big enough for my alarm, so I had him drill a hole large enough for 00g wire.

As for fusing at least 18" from the battery, that's absolutely correct, but WHY would he have to use "at least a 60 amp fuse"? Use a fuse that matches the amperage you'll be pulling through the wire. If your amp has 2 25amp fuses on the chassis, then you'll need a 50 amp fuse by the battery. If it's 2 15 amp fuses, then it's 30. And if you have 2 amps, one having 2 15 amp fuses, and 3 30 amp fuses, then you'll need a 120 amp fuse at the battery. Also, not only do you HAVE to fuse it at the battery, you SHOULD also have a fused distrobution block within 2 feet of the amps themselves.
 

·
Registered
Joined
·
791 Posts
Replying to Topic '? amp wiring'

Are there wires in that fuse box that turn on and off with the rest of the accessories?

I'm not sure of the easiest way to run that remote turn-on wire amps need, so that the amp turns off when you aren't there.

I hoping to do the entire installation (only need 8 amps) from the inside fuse box by the dead pedal.
 

·
Premium Member
Joined
·
2,898 Posts
Reading Topic: ? amp wiring

You are correct in mentioning that the fuse size should depend on power. However, I have always found it nice to have a bigger fuse than necessary so that it doesnt blow as easily.

As far as finding a good remote lead... All you need to run the remote wire is a constant 12V wire that will turn on and off with the radio. I believe there is one on the back of the factory radio now, but im not sure what color it is. This is easy to check with a meter, simply power on and off the radio and check each wire. It might be time consuming but this would be alot easier then trying to wire it into a fuse box.
 

·
Registered
Joined
·
657 Posts
Reading Topic: ? amp wiring

Having a bigger fuse than needed defeats the ENTIRE purpose of having a fuse, which would be to blow if too much power goes through it. I mean, if you have an amp that draws a max of say 40 amps, and you have a 80 amp fuse on the power line, and your power cable is only about 8g, then not only is your amp going to fry if something goes wrong, but you'll have a fire break out along your power wire. WHY? Because the fuse near the battery didn't blow. Why? Because it was rated too high.

Simple fact is, if you're matching the fuse ratings on your amps with the one at the battery and you're fuses, then something's SERIOUSLY wrong with your install. Usually, I put a fuse about 10 amps LOWER by the battery, to even further protect myself, and I never blew a fuse from playing too loud or drawing too much power. Shorts, yes, but not from listening.
 

·
Registered
Joined
·
791 Posts
Replying to Topic '? amp wiring'

QUOTE
I believe there is one on the back of the factory radio now, but im not sure what color it is. This is easy to check with a meter, simply power on and off the radio and check each wire. It might be time consuming but this would be alot easier then trying to wire it into a fuse box.[/b]
Right, there has to be a remote turn-on going to the stereo. The point was, I didn't want to have to disassemble the dash if I didn't have to. Getting to the fuse box is easy, so I thought that'd be the better approach.
 

·
Registered
Joined
·
657 Posts
Reading Topic: ? amp wiring

Do you have a link to the PSW150M? Because 8 amps of draw equals out to ABOUT 40-50 watts, which doesn't sound right at all. I mean, even the smallest class D amps draw about 30 amps.
 

·
Registered
Joined
·
464 Posts
Reading Topic: ? amp wiring

I know on some cars there is a channel that runs above the plastic wheelwell inset. If you remove this part you can run wires to the engine bay with not cutting any holes in the firewall. I'm not sure if this is possible with the 6.
 

·
Registered
Joined
·
791 Posts
Replying to Topic '? amp wiring'

QUOTE
Do you have a link to the PSW150M? Because 8 amps of draw equals out to ABOUT 40-50 watts, which doesn't sound right at all.[/b]
Nope, the PSW160M. It's 30 watts continuous per channel (DVC subwoofer); rated at 50x2 peak. The '160' in the model name probably comes from the 160mm woofer. It says max draw is 8 or 8.5 amps, and recommends a 10 amp fuse.

I was finally able to check today- these subwoofers do NOT fit under the seats. It's so close though! Oh well, back to the drawing board...
 

·
Registered
Joined
·
1,016 Posts
Reading Topic: ? amp wiring

Ok, now I can properly answer your question n-spec6....you definitely do not have to drill any holes, I just finished running my amp wiring and got a 4G power wire through the firewall with no problems. Locate the huge block of wires above your brake pedal....they all go into a rubber boot that passes through the firewall. Take your battery out, get a flathead screwdriver and locate the boot. Pry the boot from the firewall. Run the power wire outside the boot through the hole. Cut a notch on the outter edge of the boot that is big enough to accept your power wire. Reseat the boot into the frame and you are done. I could have ran a 1 guage wire through the hole if I'd felt like it. Plenty of room between the boot and the frame. Just try not to damage the boot, don't want any water leaks later. If you are really worried about water (I wouldn't be, have done this to every car I've owned never had a leak) you can get some calk or something form the auto store to apply to the edges of the boot.

Also..answer to the remote: just connet your remote turn-on to the cigarette lighter. The cigarette lighter in the center console only powers on when the ignition is turned on..and it is very easy to get to...sounds like the perfect candidate to me. I did an inline splice with the blue wire connected to the cigarette lighter, you can get the inline splices from Wal-Mart or any automotive store for about 50 cents. Took me less than 20min.

To get to the cigarette lighter, open the cupholder and pull firmly from the edges...the cupholder assembly will come right out. Then you will have to fight with the gear shift console. I had to turn the key and put it in reverse to get that console to come up. Pull it up just enough to get to the jack behind the cigarette lighter. Disconnect the jack, apply the inline splice, reconnect the jack and you are done. You will still be able to use the cigarette lighter. Also the REM current is well within the lighter's fuse range so you don't have to worry about stepping up the fuse. I'm running a 2000W+ system off the REM I hooked to the cigarette lighter.

By the way, maybe you've noticed...but from here you can also take the radio out. There are two screws located below the radio console, you have to remove the gear shift panel to see them. Loosen those two screws and the radio console kinda tilts out.
 

·
Registered
Joined
·
657 Posts
Reading Topic: ? amp wiring

You have something between the wire and the firewall, right? Bare metal + wire + rubbing = NOT good.
 

·
Registered
Joined
·
1,016 Posts
Reading Topic: ? amp wiring

There are several things you could do to protect the wire including installing grommets around the edge or wrapping the portion with tape, You can also buy a hollow threaded pipe, slide it to the section that is going to pass through the hole, put a bolt and washer on each end of the pipe and crank down on them once they are located at the pass through point

Personally I've never done either. 4G wiring has almost 1/4" thick insluation , on top of that I secure both edges with zip ties until the wire won't budge, which it won't really be able to move anyway after reseating the boot. My last setup lasted almost 3yrs.....pulled the wire back when I sold the car....hadn't even rubbed off the lettering on the wire.

Forgot to mention earlier....if you are taking the radio out...there is a 'secret' screw you have to remove . You must go through the glove box to do this.
 

·
Registered
Joined
·
1,016 Posts
Reading Topic: Reading Topic: ? amp wiring

stretchsje...I would recommed not attaching anything to the fuse box, and instead run a power wire straight from the battery. Newer cars have some circuits that are 'input sensitive'. Meaning...if the input voltage drops they react...could be anything from deploying the airbags to disabling the car.
Attaching a power lead to one of these circuits would cause the input current going into the primary circuit to drop...which could cause some very undesirable effects. Connecting directly to the battery bypasses all such circuits. I know it's a bigger pain, but it's only about 3 more feet, and if you use the rubber boot, it's easy.
Additionally if the car develops any electrical problems, the dealer may try to blame your installation...the way to stay in the clear is to stay away from the rest of the electrical systems.
 

·
Premium Member
Joined
·
5,097 Posts
Reading Topic: Reading Topic: ? amp wiring

Diesel, there are no voltage regulators in the fuse box. This means the voltage change will be the same whether you load it on the fuse or directly on the battery.

Always disconnect the battery before doing anything to your electrical system. You wouldn't want that airbag deploying in your face while leaning forward to reach a cable under the dash...
 

·
Registered
Joined
·
1,016 Posts
Reading Topic: Reading Topic: ? amp wiring

Steve 6er, ok the voltage regulator information may be correct, not sure since I've never seen a wiring diagram for the 6. However the other problem is, attaching anything to the fuse box will possibly overload the original main block wiring. If the positive wire coming off the back of the fuse box is only 4 guage and the amp alone that you are installing requires 4 guage, guess what....you will need to upgrade the main wiring to at least 2 guage to properly have a dedicated 4 guage feed running to the amp. Anything lower and you run the risk of an electrical fire.
I will still stick to my practice of always running dedicated power wires straight from the battery.
 
1 - 20 of 28 Posts
Top