How to: Installing an Amp power cable Directly from your battery.

PaulOliver · Jan 23, 2010

Right, finally Sabas guide is back up, and it’s awesome. However I’m not a fan of running my power off the 30amp supply in the back, it just doesn’t seem right to me. So here’s my how to guide to install a power cable from the battery, to the boot.
1. Get all your wiring and stuff ready.

2. Disconnect your battery.
3. Open your passenger door and pull off the side panel with your fingers.

4. Open your glove box; there will be 5 torx screws. 2 at the top, one in the middle inside the box and 2 at the bottom under the box. Slide the glove box forward and it’ll drop, be careful as you need to disconnect the terminals for your light and the hose for your air conditioner pipe.
5. You should now be left with a gaping hole. Peel back the bit of insulation circled red in the photo.

6. Now look closely and you will see a bunch of wires going through, this is how you access the engine bay. Get a small screwdriver/sharp pointed thing and pierce a hole in the thin rubber surrounding the wires.

7. Now look in your engine bay, underneath a bunch of stuff you will now see your screwdriver poking through.

8. Go get your cable, and gaffer tape some wire to it, coat hanger does the job fine.

9. Poke the wire through the hole you made with the screwdriver, depending on the size of your wire, you may need to use a bigger screwdriver to make the hole bigger, try not to make it too big, we want to keep a good seal around the cable!

10. Now look through your engine bay and find the wire, pull it through gently.

11. WOOP, we now have the cable in the engine bay.

PaulOliver · Jan 23, 2010

12.Now assemble your fuse holder onto your wiring, have about 1 foot of wire off the battery, then the fuse, then the rest of the wire.

13.Add the wire to your positive battery clamp. Tuck the amp wire in, use zip ties or whatever to keep it safe from hitting anything it shouldn’t.

14.Now you are done in the engine bay for a bit. Go get the rest of the wire and get installing!

15.The plastic strips on the floor literally just pull off, I used my fingers cos I’m hard, but some ladies like to use trim removal tools…it’s not really necessary but whatever. Start with the middle piece shown as that covers over the pieces that to either side of it. Now pull off the one that sits in the foot well.

16.Feed the wire through and underneath the carpet in the corner.

PaulOliver · Jan 23, 2010

17.Move to the back and do the same, remove the trim and tuck the wire in.
18.Now the last trim is slightly under the rear bench. Pull up the rear bench from the back; don’t remove it completely as you don’t need to. Now feed the wire under it and into the boot

19.Refit all the trims; they should click back in places perfectly. Push the rear seat back down.

20.Now you have a cable in the boot! WOOP!

21.Now follow SABAS guide and get fitting your rca cables, earth and remote.

22.Reconnect the battery.

23.Enjoy

johnaa marle · Jun 29, 2021

PaulOliver said:
17.Move to the back and do the same, remove the trim and tuck the wire in.
18.Now the last trim is slightly under the rear bench. Pull up the rear bench from the back; don’t remove it completely as you don’t need to. Now feed the wire under it and into the boot

19.Refit all the trims; they should click back in places perfectly. Push the rear seat back down.

20.Now you have a cable in the boot! WOOP!

21.Now follow SABAS guide and get fitting your rca cables, earth and remote.

22.Reconnect the battery.

23.Enjoy

Thanks for sharing very helpfull info

Cosmicflash · Jan 23, 2010

Nice write up.

You need to clean that car up

And was that nice JL Audio sub dragged thru the street or what?

PaulOliver · Jan 23, 2010

The cars filthy, it got hoovered and washed straight after the install! i only got the car a few weeks back and so thats exactly how i got it

i do take care of my cars, but i only have so much free time, so i figured id get the diy jobs over and done with before i tended to cleaning the car nicely.

The sub is about 6 years old, and had an awful life...yet remains fantastic sounding. I really couldnt care a less about its looks

its got character! Its had numerous bike pedals and beer bottles hit it. Doesnt matter anyway, they are cheap and so who cares

stevedol · Jan 23, 2010

Added to the 9-3SS ' How to ...' Section sticky

SAABalingus · Aug 10, 2012

Hey steve,
Since you're the "super moderator" maybe you can help me out. Why the heck can't i attach any photos to my posts? My whole attachment bar is green, no red at all. When I ckick manage attachments i get the 4 add boxes but none of them light up and i can't click or select them. I don't know what's going on.
Thanx for any insight you can offer.

sulloj · Jan 24, 2010

More like "how NOT to"

PaulOliver · Jan 24, 2010

Fancy elaborating?

05saab9-3 · Jan 24, 2010

well going off what the other guy said theres a few things that need to be elaborated on first you should use a ring terminal at the battery not a spade, as for the one foot its only about 6 inches for the fuse to battery and never never poke through an occupied grommet with a sharp object ever there is always a spot to drill your own hole and place your own grommet, then you have to loom your wires to protect from heat and moisture, i am a certified car electrical tech so you can trust me here i am only saying something to benefit everybody

now for the tips and tricks if your car is auto go on the driver side underdash go to where the clutch pedal would go and dril your hole you have about 3 inches all the way around from the center of the mouting position
if you car is manual move slightly left of the clutch pedal and down diagnally about 2 inches or so
pull the center console and and drill to the right of the gas pedal but left of the main grommet is another option
for remote turn on you can use ignition which is blue in the center console for saabs up to 03 06 or the cig socket always fuse this wire since our saabs have no designated amp turn on wire its all through fiberoptics
left and right audio is under the driver seat if you have a seven speaker system at the amp or at the 6x9's in the rear if equipped
as for ground scratch a little paint away and make your own ground just be clear of the gas tank
run your power wires on one side of the car and your signal rcas down the other side of the car

and the original poster i apologize if i offended you with this post im just elaborating as to why someone would say that you didnt do it the proper way just trying to help you out thats what this forums all about

PaulOliver · Jan 24, 2010

05saab93, no that’s fine, i don’t wish to distribute incorrect information and you have explained what is wrong in your opinion, which is perfectly acceptable. It’s just a bit retarded of sulloj to come here, say it’s wrong and not back up why, typical forum behaviour unfortunately.
Ring terminal over spade, that’s easily changed, although i was just using what came with the kit, what difference does it make?
The grommet, i had obviously checked the other side before ramming a screwdriver through, I’m very surprised to hear you drill a new hole. The installers i have spoken to would have taken the same route as myself, and that’s also the same way i have done it to 8 cars now with no known problems. I shall of course take note of that next time i install.

Remote from cigarette lighter...i was told specifically buy a few people on here NOT to do it that way, but i am unsure as to why not as it seemed totally fine by me.
What loom wrap do you recommend? I have never heard of anybody using it for amp wiring, and i have never seen them on 'pro' installations either on cars I’ve seen! So that’s why i didn’t use it, seems Saab also hadn’t bothered with half my car too.
Anyway, if needs be i shall edit the topic with your points, then at least everybody can decide as to what route they take.

boxman · Jan 24, 2010

every one a critic hay Paul :roll:

you might think about one of these now

its taken me 18 months to find a remote turn on for the amp in the UK, can get them in the US but this is the first I have seen here, I have ordered on so I will let you know if its any good

PaulOliver · Jan 24, 2010

Cheers for the link, thats interesting and new to me

although i have no issues running my remote off fuse 17, it works fine!

boxman · Jan 24, 2010

thats what I have dont but I dont like the amp being on all the time :roll:

fussy I guess lol

JMarkert · Jan 24, 2010

Nice write up - a question and a comment.

First, I think it's great that you located that big pass through in the firewall. Does anyone know where it might be on LHD cars? I don't think I'll put in an amp, but I could see using this pass-through.

Second, I disagree with the idea of drilling a new hole. Our cars are galvanized. That means there is a thin coating of zink on the outside of the sheet metal. Drilling a hole exposes untreated metal to the air and will destroy this protection. It's an open question whether this would be a problem over the service life of the car, but I wouldn't risk it.

zrider91r · May 2, 2011

I went under the drivers side (LH) and way up under there there is a rubber grommet with wires going through. I have a wire puller so i jammed that up there and it popped out by the shock tower. I just taped the wire to it and pulled it right through. NO ISSUES AFTER 8 MONTHS!

PaulOliver · Jan 24, 2010

jmarkert, i'd imagine yours to be on the opposite side? just take a look

glove box takes a minute to pull off so take a peek

As for rusting issues, surely a bit of metal treatment paint would suffice? Remember with a rubber grommit it should be sealed from the weather anyway and also a little silicone selant could help guarantee an air tight seal.

swissroll · Jan 24, 2010

Well i went through the existing grommet same as PO. Figure seeing as Saab had already done the drilling for me and put a nice factory fit tight grommet there - might as well use it (with rubber sealant used afterwards once cable run through). For sure one needs to take great care to avoid the factory loom but it would be real cack handed to damage it. Not sure of the purpose of looming a power cable, I just used insulation tape to bind it to the plastic cable run under the carpet to make sure it would never be a possible metal contact anywhere.

Guess I did it a little easier in that i pushed the cable through from the engine side and was able to just pull it down with my fingers from just under the glovebox, meant avoiding removing the glovebox.

05saab9-3 · Jan 25, 2010

i guess i was being misunderstood in what i said i am not saying that what he did was wrong in anyway someone else made a comment and the original poster wondered why a comment was made i stated the possible reasons i never said what he did was wrong if it works it works i was just giving possible solutions for a more professional install i really mean no harm by what i said and im sorry if it was taken in an offensive way,
as for looming the power wire its to protect the wire from heat and moving parts that can damage insulation, and as for the fuse tappers i have seen very very bad things come from that ive seen remote wires burn up and blow entire circuits its not a wrong way its just not professional and not the best method but again if it works it works i was really just providing alternatives and as for the drilling your own hole causing erosion haha seriously ive never seen it happen,and ive been doing this for long enough and ive worked on enough cars to go ahead and say thats kind of an odd thing to worry about man think of it this way take the chance of having that wire go bad and heat up enough to cause damage to other wires in the grommet or drill my own hole and still have a usuable car, and yes its extreme but its happened before just my two cents if you agree cool if not also cool it doesnt phase me as i have said i am just trying to offer an alternative method and help out i never pointed a finger and said anyone was wrong

Gs04aero · Jan 25, 2010

I agree with JMarket. Drilling a new hole is not needed. Alot of the time drilling a new hole is just laziness to finding an existing hole and grommet in the car since people dont usaully add another grommet around the power wire to seal it up. If you were to drill a new hole and use a grommet or silicone it would be fine. As for looming the wire, it is really just extra protection. There is no problem not putting any loom. Power wires come with the thick protective coating exactly so its protected. Loom is just extra cost and some extra security. I've never seen a power heat up enough to effect other wires next to it.... Paul, job was done fine in my eyes. I'm sure there could be a lot more disagreeing on the way but I see no problems with your install.

robhurlburt · Jan 25, 2010

Agreed. No need to drill another hole, use the existing hole and grommet that is there. Ring terminal is ideal, but spade is fine.

I think its an excellent write up. This is almost exaclty how I have done my cars over the past 13 years and never had an issue.

nattytread · Jan 25, 2010

Nice writeup, and good timing as I bought 2 amps this weekend that I'm getting ready to install. And yea, the stock amp2 wiring is pretty lightweight -- I'm hesitant to run even one amp (for the 6x9's or re-amped 6.5's) from that. (I think my speaker wire is comparable to the gauge of the amp2 power wire...)

I wondered though if the new power cable you pulled has adequate clearance when run into the trunk/boot behind the seat? It'd be awful if the seat were to pinch it enough to pierce the cable jacket when lowering/raising the seat back.

Did you try to run it behind the interior panel alongside the seat and through the parcel shelf where the existing wire loom runs? Does anyone know if there is enough room to do this?

swissroll · Jan 25, 2010

nattytread said:
I wondered though if the new power cable you pulled has adequate clearance when run into the trunk/boot behind the seat? It'd be awful if the seat were to pinch it enough to pierce the cable jacket when lowering/raising the seat back.

Did you try to run it behind the interior panel alongside the seat and through the parcel shelf where the existing wire loom runs? Does anyone know if there is enough room to do this?

I dont know what Paul did but for me as I have 2 new amps I ran the cable into the space where the boot fuse blocks sit and would house the amps for the ES3? factory fit Saab supplied amps if it were there. Then I ran the power via a splitter/fuse block back to the amps now located on the rear of the back seat with a little 'play' to allow for dropping the seat ( and a protective cage for the amps..). Means removing the seat bolster in front of the seat belt - very easy, and running the power cable up and through the large gap behind the seatbelt, very obvious as its where all the existing Saab cables run.

Cafasco · May 2, 2011

Ok great write up! I did it like Paul did...poke a thin small screwdriver though the exsisting main wire harness rubber grommet.

The hard part is the main wire harness is on the same side, so for LHD cars on this side of the pond its up and to the far left up under the steering column. its is not a lot of fun. Everything else looks the same...you just cant axcess the wire harness via the glove box, so there is plenty of body contortionism to get up in there and get the wire though the firewall.

I prefer this method over drilling a hole as well...

Xplode · Aug 21, 2011

Hey, awesome write up, I just did this myself over the weekend, your guide was very helpful, I have installed amps in many other cars, but never with the factory head unit, was good to have the guide.

Just 1 question, as Im still waiting for my line out converters to arrive, i haven't finished the set up.

How did you run the cable from fuse 17, and are you talking about the fuse in the boot, for the rain sensors/sunroof. This is the only fuse I found in the car that is only on when the key is in the ignition so i would love to use that for the amp remote.

Any chance of a bit of a guide on how to connect that up.

PaulOliver · Aug 21, 2011

Glad to know so many people have benefitted from this

for the remote lead to fuse 17, i literally removed the fuse, whacked in the remote wire and replaced the fuse so that the blades forced the wire into the slot. A slightly less bodgy way of doing this is to buy an 'add a fuse' of which it piggbacks off the fuse and fives your remote wire its own seperate supply with its own independant fuse

Lexx0r · Aug 25, 2011

the RCA just goes straight into fuse 17? from the amp? does the amp then run when the cars off? I dont understand this RCA stuff

Xplode · Aug 21, 2011

Awesome thank you so much.

Really did not expect a reply, let alone that quick, considering the thread started in 2009 lol.

I will try it out as soon as my line out converter's get here, I may just do as you did and jam the cable in.

Really appreciate the help, I thought i was screwed when the factory amp blew, and no aftermarket head units are available to fit this car.

Following your pics it took me literally 15 mins to run the power from the battery.

The only problem I ran into was bypassing the fiber optics from the AMP1, at the moment their just sitting in a tube facing each other, but occasionally I will get some popping noise coming from the speakers, any suggestions?
Also, your fuse 17 was the 7.5A for the rain sensors/sunroof yes? Just want to confirm that 7.5A will be enough to handle the amp remote.

Again thank you for the prompt reply, and I will post pics on this thread of the remote connection once it is done next weekend hopefully.

PaulOliver · Aug 25, 2011

No, the rca comes off amp 1, the remote lead tells the amp to turn on when the car is started.

Xplode · Aug 26, 2011

RCA is the audio signal into your amplifier, the lead from fuse 17 goes to the remote connection on your amp, this tells your amp when to turn on, and when to turn off. I found that fuse 17 from the rear fuse panel works best, (with guidance from PaulOliver) because this is only on when the car is on. Therefore it will turn off the amp and not drain the battery.

I took my RCA leads from the rear speakers, however I am only using this amp to power the 4 speakers on the parcel tray, I bought 2 6x9s and the original 4" speakers.

Lexx0r · Aug 26, 2011

r.e

Xplode said:
RCA is the audio signal into your amplifier, the lead from fuse 17 goes to the remote connection on your amp, this tells your amp when to turn on, and when to turn off. I found that fuse 17 from the rear fuse panel works best, (with guidance from PaulOliver) because this is only on when the car is on. Therefore it will turn off the amp and not drain the battery.

I took my RCA leads from the rear speakers, however I am only using this amp to power the 4 speakers on the parcel tray, I bought 2 6x9s and the original 4" speakers.

Right so I had two little 4" speakers in the back, so can someone be kind enough to explain how I am wiring up?

Take power from the battery - wire this directly too my sub/amp?
RCA from audioleads from the 4"?
Line convertors? Where?

Jesus this is confusing haha! First time dealing with these!

Xplode · Aug 26, 2011

Paul, any suggestions about a popping noise coming from the speakers, (occasionally, only when the car has sat in the cold for a while)

The popping bounces from speaker to speaker, its not from all at once.
It gets louder with higher volume.

How to: Installing an Amp power cable Directly from your battery.

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