Pepp

I want to install new front component and new rear speakers from a aftermarket amp that I am placing in the cargo area. A Crutchfield advisor informed me I could cut right into the factory speaker wire back at the factory amp. Then I could have my crossovers right in back in the cargo area. I would also only have to run my wiring from the new amp to the old amp which would only be a couple of feet instead of running the wire all the way upfront and having to find a place for the crossovers. Sounds great. I'm just a little nervous cutting the wire at the factory amp. Has anyone done this and did you experience any problems? As far as I know the factory amp will not be used at all. I am installing a new head unit,4 channel amp, a mono amp, and new speakers and a sub.

List of new stuff:
Kenwood DPX702BH head unit
Alpine F300 4 channel amp
Alpine mrv500 mono amp
Infinity reference 6030cs component speakers
Focal Auditor RCX 165 speakers
Alpine SWS 10D4 10 inch subwoofer

05RX330AWD

If the original amplifier is not used, you may lose the sounds as the chimes, the voice for Navigation & the controls for the steering wheel....
as you may not have all the connections & features available on the new gear listed. You will need some harnesses, as the Metra brand.
Although other CL Members should confirm this, possibly current equipment may have more to offer for installations in Lexus vehicles.
Cutting the wire of the original amp shouldn't be an issue if hooked up or insulated correctly.

rich001

If your RX is a 04-09, non-Nav, you can get the speaker wiring at the rear amplifier. At the factory amplifier you'll find 6 pairs of speaker wires (L rear, R rear, L front door, R front door, L dash and R dash). You can do a search and get the correct color codes before hand so it's easier for you when you start cutting the wires. I would have wire extensions ready (length depending on where you are mounting your 4-ch. amplifier or your crossovers). You can get to the amplifier behind the rear seat by removing carpeted panels, it's located under a black brace, and move the rear seat forward.
You will not lose chimes, as for steering wheel controls, you can get a Axxess ASWC-1 interface or PAC SWI-RC. You will still need to run three RCA's front to rear and a remote turn-on lead for the amplifiers.
Here is what I had for a 2005 Lexus RX330, Non-Nav:Car Radio Battery Constant 12v+ Wire: Blue/BlackPIN 1
Car Radio Accessory Switched 12v+ Wire: GrayPIN 11
Car Radio Ground Wire: BrownPIN 20
Car Radio Illumination Wire: GreenPIN 2
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: OrangePIN 13
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: Amplifier is located under the passenger side rear seat.At Factory Amplifier: Dual White 16ga. Wires are 12V+ Constant,Dual White/ Black 18ga. Wires are Ground(These Wires Are NOT Used)Did NOT add Resistor that came with the 99-8159S Kit
Left Front Speaker (Dash) Positive Wire (+): Brown4.2 ohm
Left Front Speaker (Dash) Negative Wire (-): Red/YellowLeft Front Speaker (DOOR) Positive Wire (+): Purple3.2 ohm
Left Front Speaker (DOOR) Negative Wire (-): White
Right Front Speaker (Dash) Positive Wire (+): Violet4.2 ohm
Right Front Speaker Negative (Dash) Wire (-): PinkRight Front Speaker (DOOR) Positive Wire (+): Pink3.2 ohm
Right Front Speaker Negative (DOOR) Wire (-): Blue/ Black
Left Rear Speaker Positive Wire (+): Red4 ohm
Left Rear Speaker Negative Wire (-): Gray
Right Rear Speaker Positive Wire (+): Red/Yellow4 ohm
Right Rear Speaker Negative Wire (-): Blue

05RX330AWD

rich001 Apparently Pepp mentioned he will not use the factory amp, therefore will lose the chimes if he doesn't get an appropriate harness.
Unknown if he has Nav or not & if $$$$ is no issue, Beat-Sonic is an all- in- one easy install option.

Lexuswiz

iTrader: (1)

What you are doing is fine but you should leave slack on the stock amp side just incase you ever need to reconnect the speakers to the stock amp. Personally, I'd run new wires to all the speakers, if you're going to invest all that money into amps and speakers only to have it bottlenecked by the thin OEM wires, kills it for me.

You will lose the steering wheel controls unless you have a steering control module, regardless if you have Nav or not.

Pepp

I would definitely prefer to run the wire directly from the amp to the speakers. The problem is getting the wire into the door. The feeder tube ( hose going from car to door that wires run through) is not an open tube, it actually has a plug on the one end so you can't fish a wire thru. I already purchased true 14 gauge wire and ran it from the amp to the doors when I ran all the power and RCA cables. Much to my disappointment when I tried to feed my feeder stick ( a plastic plant hanger rod which works great and my wife has a ton of) it wouldn't go through the hose. Would much rather hook up directly because I know I'll be loosing wattage from the amp with the cheap 20 awg wiring. If you know how I can run the wiring directly without any major fabrication ( a little is ok) it would be greatly appreciated

Pepp

Rich001 thanks for the info. I most likely will take this route. It does put me at ease having to cut the amp wires. If it was a 74 pinto(hopefully you know that car) I wouldn't worry so much. But with the Lexus you never know what is connected to what electricly.

Lexuswiz

iTrader: (1)

Hmmm.... strange, I ran 2 20 gauge wire to my drivers door for the alarm side of my remote start with no issues using 26 gauge steel wire as a feeder. But I only touched the drivers door, not sure about the other doors, but i'd assume the same. Was tricky but I've seen worse in Benz's.

I'll need to pull the kick panel to recall what I did exactly, it's been a few months. I hope to get a response to you by this weekend.

Pepp

When I attempted to feed the wire and it wouldn't go through I pulled the grommet out a little from the car side and it appeared to be more of a plug then an open ended tube. Did you try running from the door to kick panel or vise versa ? Perhaps my fisher was too thick and a thin piece of wire like you used would work better. May I ask exactly what Lexus you drive. Maybe I can find out if there are any changes between models or years. I lean toward there wouldn't be any major modifications unless it was a total model change. I appreciate you taking the time to check this for me, I already sealed the inside door panels with Dynomat but willing to remove to attempt to get the wires through. My understanding is if I splice into the original wiring I'll be losing somewhere between 20 to 30 percent of my amps wattage ( so I've been told, as I don't know this from any educational electrical experience).

rich001

Pepp, you'll be fine with using the speaker wires at the factory amplifier, you will not hear nor notice any difference than if you ran new 14ga. wire to each speaker. Plus you are using an Alpine MRV-F300 amp, nothing really high power or high end. Also, your chimes will function as normal, they do not go thru the factory amplifier.

Lexuswiz

iTrader: (1)

2005 RX330 AWD with Nav. Will put some sounds in it eventually but pretty content with the stock system, car isn't driven much.

I remember running it from kick panel to door on the drivers side as most of the wiring I did for the remote start was in that area. A thick solid metal feeder really helps, I could never use plastic. I recall the ends of the door wire loom has plugs but the loom was not closed and could take wire. My daily is my Camry so when I have the RX parked I'll take a peek again.

Although this is 100 percent accurate, from personal experience, it just sucks to have to do it later on IF Pepp was to upgrade to a higher end system which I am in this predicament now with my Camry. I'm literally ruining the clips on the doors from constant removal and replacement. But if Pepp is content with the sound, stock wire will be perfectly fine. My days of being cheap and lazy are finally catching up to me.

Pepp

Lexuswiz I always have a bad habit of breaking door clips when removing door panels, even with the pry tool. I went on Amazon prior to starting install and purchased a pack of exact fit door clips for about $7 bucks. There is a nice inexpensive alternative to Dynamat as well. It's called Peel and Seal which is available at Lowes. You can either buy a small roll for about $16 or do like I did and and purchased a roll of 36" x 30' for $97 to do your whole car. I was able to cover all my door panels(inside and out) plus enough for the cargo area. If you read the reviews it seems like more people use it for sound deadening than roofing. It is aluminum backed asfault. The professional install shop by my home stated the original Dynomat was asfault backed prior to the new stuff they have now(Dynomat extreme?). I experienced absolutely no odor when I installed it and it was about 90 outside. The difference inside the car is night and day.

05RX330AWD

I have never had the opportunity to remove the door panels although have removed the tailgate panel.
Same here, broke some clips, if the door panel clips are the white ones as found in the tailgate panel.....
I removed 20 red clips from Toyotas at the Wreckers, I was able to use for the tailgate panel, total price: $1.

Lexuswiz

iTrader: (1)

Finally pulled the kick. I definitely used a steel feeder. The door tube is open and the plugs are on the kick panel side. I have attached a few crappy pics to show what I fed, I apologize for the quality and position it sucks tucking my body in that drivers footwell area to wire stuff let alone to take pics. Wire is smaller then I remembered, as it just to send the unlock/lock pulse but I can see a 16 to 14 gauge wire being fed through it, there's plenty of space.

Here is the full door jam, to show I didn't feed it through a seperate grommet:



Here's the hole in the kick side that the door harness comes in:



Here's a close pic of the feed wire (green and blue):








Thanks for the tip, been meaning to buy a pack of clips, I just keep forgetting. Also heard of that mat too, isn't it for dampening shower floors? Might try that in my Camry.

Pepp

Lexuswiz I think I see what you mean. Do the wires feed through the black tube or run along the side? I will be removing the kick panel and taking a better look tomorrow to see if I can match up what I'm looking at. Hopefully if I can feed it this way I won't have to remove the Dynomat. I might be able to reach up through the speaker hole.