03limited2WD
New member
This is how I replaced the stock JBL Sub-woofer speaker and Single Disc RDS JBL Synthesis Radio, while retaining the rest of the JBL sound system. I did not want to add any amplifiers and I did not want to run any additional wires. I plan to add a backup camera later, and possibly aux video.
This is a pretty good Bang-for-the-Buck project, as long as your stock JBL speakers are in working order. I had to replace my stock sub-woofer, but in my opinion, replacing the JBL Stock HU alone will make a huge difference in audio quality and system volume.
This is not intended as a step-by-step walk through of every aspect, just an overview of what I felt were the most important discoveries during this process.
So, when I bought my new (to me) 2003 Limited with a JBL Synthesis Single Disc RDS, there was a definitive lack of bass frequencies. It turned out that my stock JBL sub-woofer driver had completely disintegrated its own rubber surround. This original sub-woofer had spit out its last sine wave. I decided to replace not only the sub, but the head unit as well.
This is what I used: (less than $500 total)
PAC SWI-RC
PAC TATO
Scosche TA2079B
Kicker CompVR8 (CVR8) 2-Ohm DVC
JVC KW-AV61BT
<a href="http://www.toyota-4runner.org/4th-gen-t4rs/82995-how-access-remove-subwoofer.html">I used this link to remove the sub-woofer enclosure</a>
<a href="http://www.castulucci.com/projects/carpc/oemnaviaccess/">And this link to disassemble the dash</a>
In order to retain the steering wheel controls I purchased a PAC SWI-RC (depending on your head unit, a PAC SWI-JACK may be more appropriate) and to duplicate the digital control signals necessary to drive the stock JBL amp, a PAC TATO would also be required. These 2 PAC devices came with all the required wiring harnesses that would be needed to 100% integrate an aftermarket JVC A/V Receiver Head Unit into the stock Toyota wiring. No additional wiring harness was needed.
Before you begin, set your stock stereo at zero for all of the bass treble fader and balance controls. I turned off the JBL “Surround” option also. Turn your stereo up all the way, (that was “62” on my unit) The installation manual for the PAC TATO states to turn the stereo up to “at least ¾ volume”. I turned it up to 100% and had excellent results. Otherwise, follow the directions that come with your PAC devices.
My only other advice regarding the HU is to set the PAC SWI-RC rotary selector to the manufacturer of your aftermarket stereo, not the OEM setting. The PAC website is a little confusing and suggested that I set the SWI-RC to the Stock OEM Toyota setting and when I did, the steering wheel controls would not work with the new stereo. Once I set the SWI-RC for the aftermarket (JVC) everything worked great.
I chose the Kicker CompVR8 Sub-woofer because it was the only speaker I was willing to spend money on that would fit in the stock box and match the JBL amp. It is a Dual Voice coil (2 Ohm per coil) 8 Inch Sub-woofer, that cost less than $80.
Note that the Kicker bolt pattern does NOT match the stock box. You will need to either reuse the plastic top piece off of the stock JBL sub-woofer speaker like I did, or fabricate a shim to mount between the box and the Kicker.
The new sub-woofer was far too deep to fit, and I did have to grind away much of the plastic ribbing inside the enclosure to make room for the larger magnet. I used an electric cordless drill and a “grinding wheel” bit that I picked up at a home improvement store. Since the Kicker ended up sticking out about ½ inch more from the speaker box, I also ended up using this grinding bit to remove much of the plastic ridge that runs around the circumference of the speaker “trim panel grill”, located on the back side of the interior trim piece which fits directly over the sub-woofer once everything is back together.
I filled the cavity of the sub-woofer box with loose Poly Fiber. I used “Poly-Fill” Brand, 100% Premium Polyester Fiber Fill which I picked up a 20oz bag at a “Arts & Crafts”, “Hobby Lobby” type store for about $5. More than enough for 10 boxes. This will kill any standing waves and will tighten up the bass a bit. It is worth doing if you are already going through the trouble of taking this enclosure apart.
I found this info important to rewire the new sub: This is a picture of the 4 pin harness that is attached to the Sub enclosure and directly feeds the speaker from the 4 wires that pass through the enclosure and runs inside the box to the speaker terminals. I had to remove the connector at the speaker side and strip back to the bare wire to make my connections to the Kicker. Match the wire colors to the pin-out to identify your Left & Right Positive/Negative. This is very important. If you reverse the polarity of the voice coils you will most likely cancel out all of your bass, depending on the mix of the song. You also want all of your speakers in the truck to be “pushing” and “pulling” in sync with one another. I can only verify that this is the wiring for a 2003-2004, any other years may be different.
As mentioned earlier, I reused the round plastic “top piece” that was attached to the metal rim of the old speaker, as a spacer to give a little more clearance for the new speaker. This “top piece” has the stock bolt pattern molded into it, and I off-set the Kicker from the stock bolt pattern to get some “meat” to make my pilot holes in, and to mount the new sub-woofer to the box. I used RTV silicone sealant to fill any gaps and cover the screws. Let the RTV set for at least 24 hours before installation back into the truck. We want to seal the box against any air leaks as much as possible. After the speaker was installed in the box, I glued the stock foam pad back onto the top of the new speaker. This foam was glued to the top of the old speaker, and fits tight against the interior trim piece (which I had grinded down earlier). I wanted to minimize any rattles and keep as much of the original Toyota parts as possible.
The new Kicker speaker sounds full and well balanced with the existing JBL system. Bass is louder than what I have heard from other Synthesis systems. The Stock JBL amp has plenty of power and I can drive the system well past what the stock RDS head unit was capable of. Without clipping or distortion. The bass is deep and my 4Runner has kept its stock appearance, with the exception of the touchscreen, which is definitely an upgrade from the old unit.
The center channel speaker and the rear, upper tweeters all work, and the overall sound is far, far better than what I had before. The Stock JBL head unit does not do any justice to the stock speakers and amp. I would go so far as to surmise that by just replacing the head unit and using the PAC TATO the sound system would be of noticeably significant higher quality, so long as your existing speakers are not blown.
I have had this system in place for about 8 weeks now, with no issues.
This is a pretty good Bang-for-the-Buck project, as long as your stock JBL speakers are in working order. I had to replace my stock sub-woofer, but in my opinion, replacing the JBL Stock HU alone will make a huge difference in audio quality and system volume.
This is not intended as a step-by-step walk through of every aspect, just an overview of what I felt were the most important discoveries during this process.
So, when I bought my new (to me) 2003 Limited with a JBL Synthesis Single Disc RDS, there was a definitive lack of bass frequencies. It turned out that my stock JBL sub-woofer driver had completely disintegrated its own rubber surround. This original sub-woofer had spit out its last sine wave. I decided to replace not only the sub, but the head unit as well.
This is what I used: (less than $500 total)
PAC SWI-RC
PAC TATO
Scosche TA2079B
Kicker CompVR8 (CVR8) 2-Ohm DVC
JVC KW-AV61BT
<a href="http://www.toyota-4runner.org/4th-gen-t4rs/82995-how-access-remove-subwoofer.html">I used this link to remove the sub-woofer enclosure</a>
<a href="http://www.castulucci.com/projects/carpc/oemnaviaccess/">And this link to disassemble the dash</a>
In order to retain the steering wheel controls I purchased a PAC SWI-RC (depending on your head unit, a PAC SWI-JACK may be more appropriate) and to duplicate the digital control signals necessary to drive the stock JBL amp, a PAC TATO would also be required. These 2 PAC devices came with all the required wiring harnesses that would be needed to 100% integrate an aftermarket JVC A/V Receiver Head Unit into the stock Toyota wiring. No additional wiring harness was needed.
Before you begin, set your stock stereo at zero for all of the bass treble fader and balance controls. I turned off the JBL “Surround” option also. Turn your stereo up all the way, (that was “62” on my unit) The installation manual for the PAC TATO states to turn the stereo up to “at least ¾ volume”. I turned it up to 100% and had excellent results. Otherwise, follow the directions that come with your PAC devices.
My only other advice regarding the HU is to set the PAC SWI-RC rotary selector to the manufacturer of your aftermarket stereo, not the OEM setting. The PAC website is a little confusing and suggested that I set the SWI-RC to the Stock OEM Toyota setting and when I did, the steering wheel controls would not work with the new stereo. Once I set the SWI-RC for the aftermarket (JVC) everything worked great.
I chose the Kicker CompVR8 Sub-woofer because it was the only speaker I was willing to spend money on that would fit in the stock box and match the JBL amp. It is a Dual Voice coil (2 Ohm per coil) 8 Inch Sub-woofer, that cost less than $80.
Note that the Kicker bolt pattern does NOT match the stock box. You will need to either reuse the plastic top piece off of the stock JBL sub-woofer speaker like I did, or fabricate a shim to mount between the box and the Kicker.
The new sub-woofer was far too deep to fit, and I did have to grind away much of the plastic ribbing inside the enclosure to make room for the larger magnet. I used an electric cordless drill and a “grinding wheel” bit that I picked up at a home improvement store. Since the Kicker ended up sticking out about ½ inch more from the speaker box, I also ended up using this grinding bit to remove much of the plastic ridge that runs around the circumference of the speaker “trim panel grill”, located on the back side of the interior trim piece which fits directly over the sub-woofer once everything is back together.
I filled the cavity of the sub-woofer box with loose Poly Fiber. I used “Poly-Fill” Brand, 100% Premium Polyester Fiber Fill which I picked up a 20oz bag at a “Arts & Crafts”, “Hobby Lobby” type store for about $5. More than enough for 10 boxes. This will kill any standing waves and will tighten up the bass a bit. It is worth doing if you are already going through the trouble of taking this enclosure apart.
I found this info important to rewire the new sub: This is a picture of the 4 pin harness that is attached to the Sub enclosure and directly feeds the speaker from the 4 wires that pass through the enclosure and runs inside the box to the speaker terminals. I had to remove the connector at the speaker side and strip back to the bare wire to make my connections to the Kicker. Match the wire colors to the pin-out to identify your Left & Right Positive/Negative. This is very important. If you reverse the polarity of the voice coils you will most likely cancel out all of your bass, depending on the mix of the song. You also want all of your speakers in the truck to be “pushing” and “pulling” in sync with one another. I can only verify that this is the wiring for a 2003-2004, any other years may be different.
As mentioned earlier, I reused the round plastic “top piece” that was attached to the metal rim of the old speaker, as a spacer to give a little more clearance for the new speaker. This “top piece” has the stock bolt pattern molded into it, and I off-set the Kicker from the stock bolt pattern to get some “meat” to make my pilot holes in, and to mount the new sub-woofer to the box. I used RTV silicone sealant to fill any gaps and cover the screws. Let the RTV set for at least 24 hours before installation back into the truck. We want to seal the box against any air leaks as much as possible. After the speaker was installed in the box, I glued the stock foam pad back onto the top of the new speaker. This foam was glued to the top of the old speaker, and fits tight against the interior trim piece (which I had grinded down earlier). I wanted to minimize any rattles and keep as much of the original Toyota parts as possible.
The new Kicker speaker sounds full and well balanced with the existing JBL system. Bass is louder than what I have heard from other Synthesis systems. The Stock JBL amp has plenty of power and I can drive the system well past what the stock RDS head unit was capable of. Without clipping or distortion. The bass is deep and my 4Runner has kept its stock appearance, with the exception of the touchscreen, which is definitely an upgrade from the old unit.
The center channel speaker and the rear, upper tweeters all work, and the overall sound is far, far better than what I had before. The Stock JBL head unit does not do any justice to the stock speakers and amp. I would go so far as to surmise that by just replacing the head unit and using the PAC TATO the sound system would be of noticeably significant higher quality, so long as your existing speakers are not blown.
I have had this system in place for about 8 weeks now, with no issues.
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