Hey all. I’m new here as a member. I’ve read these forums for a while though, ever since finding an interest in GS/Aristo and Soarer/SC.

Ive owned my 2004 GS300 for a few months now and I’m loving the car.

My GS has the factory nav unit which I am trying to replace with an Xtrons android system. (https://rover.ebay.com/rover/0/0/0?m...2F153404562364)

For anyone interested: I bought a JDM Aristo climate control unit which fits nicely above the 2 din stereo. All the air con functions work well, the 2 big connectors plug straight in. The Aristo climate control unit (multi function display) has a small 3rd socket which I believe reads information about things such as fuel consumption, this can just be left out.

Here are the things I would appreciate some help/advice with:

-Does anyone have a link to a wiring diagram for the OEM nav unit / stereo? Most of the old posts on here have expired links. I’m mainly chasing the wire for antenna control, amp on/off and constant 12v.

-Could the OEM amp be used by sending line level signal to it for audio along with a 12v switch to switch it on? (12v Coming from the aftermarket unit or custom fitted 12v switch? Or does it need a dry contact to turn on?)

-Does the OEM amp get powered by the OEM stereo or does it have its own supply of power from elsewhere?

-Does the amp take one line level signal and split it between the different sets of speaker outputs or does it require a pair for each speaker?

-Would it be possible to use the OEM GPS antenna with the aftermarket unit? Any impedance matching required?

 

The extra plug id for yhe 6 radio presets on the jdm head unit.
In the jdm, you access speaker inputs in the trunk. Two plugs. A 4 wire where only 2 used for subs and a 16 or more as center splr may be there.

Been a while but std toyota adapters from axiss fit both. That s in the trunk as the head unit are actually like a remote control for the units in thr trunk. Tuner tv amp nav etc.

Not sure how non jdm worked or works but you go brave and use the 9volt battery to find spkr wires. Especially the 4 pin for the sub as two of the 4 carry power and can damage the head unit if you power up your spkr output with 12v

Again my jdm with nav experience

I forgot to mention that driver door speaker passes through orignal nav. So there are 4 wires going to nav. 2 pairs similatly coloured. I think blue / red and blue /black.
jumper them similarly colored to bypass nav.
My buddy had his with an oem subharness. See pic

The four on the left

See where the are joined. Some Aristos with jdm nav dont have tlitbas a sybharness as direct into nav unit

 

Thanks for the info mate.

I ended up returning the Xtrons because it didn’t spit out any audio - amped or line level. They admitted this is a known issue (yet they still sell them). The idea of a versatile, fully unlocked android system was alluring but too good to be true in this case.

I did some detective work with a multimeter and buzzing speaker wires with another amp to locate everything. I just soldered every wire individually as the metra iso harness I got was way off what is required.

I put in a kenwood head unit and got it working including antenna control. Only thing I couldn’t find was the reverse wire in the drivers kick panel for reverse cam trigger - it’s a tight space, not much slack on the wires, so I just settled for the manual switch on the head unit to trigger the cam.

Something I couldn’t understand was the wire for the front right speaker was a pink and purple pair in the boot, while the rest of the speaker wires were found behind the glove box. There was a blue pair running from the boot to the glove box, it didn’t have any continuity and didn’t seem to do anything so I joined the pink/purple pair to it so I was able to wire the front right speaker from the glove box as well.

Any my suggestions for where to put the wired mic for a “clean install”?

My next point of call is replacing the factory sub with an aftermarket 10” and putting another sub in the boot. I’m hoping to utilise some of the wires in the boot that were plugged into the CD changer, even if I have to double up the wires to support the amps coming in. Anyone know if that would work?

Does anyone know if I have to wire the sub amp directly to the battery to support it or would I be able to use 12v from behind the stereo? Possibly from a pair that supplied 12v to the factory nav or CD changer in the boot? Is fuse tapping another option?

Heres a pic, still yet to put the ashtray in as I want to mount 2 USB sockets and a switch for manual antenna control (head unit only puts antenna down if turned off, even if not using radio)

 

I attached the mic for my system up behind the rear view mirror where you don't notice it. Being in the center also helps to reduce the wind noise with the windows down and maintain call quality. You can tuck the mic wire between the headliner and the roof and then under the A-pillar trim and run it under the dash to your head unit. That will keep the cord totally hidden except for the little bit that sticks out where the mic is mounted to the windshield.

You need to do your homework about wiring up a sub before you even think about starting this. Seriously. It MUST be connected directly to the battery on its own cable and it MUST have its own fuse. You CANNOT use any factory wires unless you're going for a tiny under powered sub. Doing anything but this and your are literally begging to burn your car down when the wires heat up and melt or if theres a short circuit. Spend the $15-30 on a dedicated cable for your aftermarket sub.

 

Thanks for the tips mate. That’s super helpful.

It all makes sense and now I get why the sub amp has the remote input to turn it on, so that it’s not draining the battery 24/7. I’m not looking for an obnoxious bass boosted sound, just enough for a balanced sound. Found 2 fusion 10” subs and an amp for $50 so I’ll just roll with that and adjust the gain accordingly. Will post updates when the job is done. I’m loving the support from the community here.

Will the sub amp amp significantly reduce the lifespan of my battery? Ie. drain it faster than it can be recharged.

Any reccomended wattage for a moderate balanced sound? From memory, it’s better to use a higher wattage amp at half gain than a lower wattage amp at full gain to avoid distorting the signal too much.

Does the fuse need to be in series direct from the battery or is the fuse on the amp sufficient?

IMO the factory speakers in the doors sound really nice paired with my Kenwood amp and some EQ. I think they do a good job of the ~150hz+ frequencies. They just need to be complemented by a sub pushing air for the low frequencies, as the car sound system was originally designed to work. It’s passable without a sub but it’s definitely a bright sound and not as full as I’d like it to be.

 

The battery lifespan won't be affected unless you're always turning everything up to 11.

The rule of thumb I've seen is about 50/50 on wattage. So 50% of the total wattage goes to the sub and the other 50% goes to the speakers. If you're using the factory speakers even 300W is too much and 2 10s will absolutely over power them.

Always fuse as close to where you connect to the battery as possible in addition to the amp. The reason is if the wire were to break between the battery and the amp and short, then if theres just a fuse at the amp theres nothing to stop the flow of current between the batty and amp and your car burns down. Do some research on wire sizing as it depends on the distance you run vs current as to which gauge you need.