AWehland88

I recently installed an aftermarket radio into my 1998 Lexus es300. I, like many people, didn't want to spend big $$ at a shop to get them to put it in for me. However...Lexus is a PAIN to modify, (even the older models) and I couldn't find a thread that was newer than 2005 on the subject, so now that I have successfully done it, I am going to do my own write up. I hope that this thread helps save some of you from having to look for hours online.

I installed a single din Pioneer DEH-150 stereo and used a metra harness and dash kit. Links below...

Stereo:
Harness:
Dash Kit:
Tools you will need:
Wire Cutter/Stripper
Flat Head Screwdriver
Phillips Head Screw driver
Socket Set or Wrench 10mm
Speaker Wire
Electrical tape or crimps

1) We need to start by disconnecting the battery terminals from the car. this will ensure that nothing will short and the airbag won't deploy while you are working around the glove box area.

2) Remove one of the top air vents from the air console above the stock radio, then carefully pull the rest of the air vent cover system out and disconnect the two harnesses attached to the back of it. You will see two bolts that hold in the radio. Then underneath the climate control console and above the ashtray/cigarette lighter, pry off the small trim piece. You may have to pull out the cigarette holder and ashtray to get at the bolts, but I didn't, so I just left it on.

3) Unscrew the bolts that hold in the climate control and stock radio and pull the whole thing out towards you. When it comes free, disconnect all 4 harnesses and the 2 antennas in the radio/climate control.



4)There will be a bracket on the side that connects the climate control and the stock radio together. Unscrew all screws with your Phillips head, and set the stock radio and cage off to the side, you will not need them anymore. Use the instructions that come with the metra dash kit to assemble it. You will need to re-use the screws that you took out of the stock radio and cage in order to assemble your new radio into the dash kit, so don't discard them!

5) Take your metra wiring harness, as well as your harness for your aftermarket radio (in my case the pioneer deh-150) and color match the available wires. Black to Black, Yellow to Yellow, Red to Red, Blue/White to Blue/White etc. Be sure to tape up or crimp cap the wires where you connected them. At this stage in the installation I was left with the 4 RCA plugs, and a blue wire on my metra harness(my aftermarket radio didn't have the blue antenna wire) and white/white black, green/green black. purple/purple black, and gray/gray black on the aftermarket radio harness. Leave the wires on the aftermarket harness alone for, we will come back to it later. Using your wire cutters, cut away the RCA port wires and tape the ends of them, along with the end of the unused blue wire because they will not work! Trust me, I tried plug and play and it will not happen! after doing all of this, connect your metra harness to your factory radio plug, and connect your aftermarket harness and the large antenna to your aftermarket radio. Plug the battery in and make sure that the radio turns on. You will not hear music clearly yet. If it works, then disconnect the battery again, and proceed to stop 6. If not, check the connection of your wires again.

In order for the sound to play through the speakers, we will have to bypass the factory amplifier in your Lexus. In order to get to the amp in the 98 es300, you have to take apart the gloveboxcause it is behind there. I should note that my particular car did not have a cd player in the glove ox like many of the es300 models, so additional steps may have to be taken to remove that if you can not get to your amplifier by just the steps I will outline.

6) Open your glove box to reveal 3 Phillips Head screws holding it in. Remove these. There is a bolt holding in the underside of the glove box panel, and in order to get to it, you will have to remove the trim on the door frame...it should just pop off. Once you reveal the bolt, remove it and pull the glove box gently out. There will be 2 harnesses that connect to the glove box/air bag, disconnect them and pull the box all the way out.

7) Locate the amplifier. you will not have to remove the amp, Remove the two smaller harnesses.



This diagram will help you figure out which wires I am talking about, so when I refer to numbers, please look at that. Leave harness A where it is. It sends power to the headunit. let's start with harness B. As you can see from the diagram it is responsible for the rear speakers. Cut a length of speaker wire that is long enough to reach from the glove box to the headunit. In diagram B locate wires 1 and 3 and cut them. Connect the speaker wire to each wire respectively. I used the negative side of the speaker wire with wire 3 and the positive with wire 1 just to make it easier to identify on the other end Tape them off or crimp cap them. Snake the speaker wire through the glove box and into the empty space where the aftermarket radio will be. Connect wire 1 to the purple wire in the aftermarket harness and wire 3 to the purple black. Repeat with the rest of the wire connections as shown here.

Harness B
Slot 1 to Purple
Slot 3 to Purple/Black
Slot 2 to Green
Slot 6 to Green/Black

Harness C
Slot 1 to Gray
Slot 5 to Gray/Black
Slot 2 to White
Slot 6 to White/Black

8) Once you have all the connections taped up and threaded through in place, reconnect the battery and test for function. At this point all your speakers should sound normal and all of your components on your radio should work well. Secure your connections by zip tying or wrapping a few strands of electrical tape to keep the wires together. Put your glovebox back together by reversing the process you took it apart in. Install the metra dash kit into the empty radio slot according to the instructions in the manual it came with, then reassemble the climate control and air vents back together. Reconnect the battery again if you disconnected it to reassemble, and enjoy your new radio!

I hope that this updated thread will help some of you with older model lexus es300 cars.

jay92

Thanx for the help just wondering if Im supposed to keep harnace B and harness C in the diagrams plugged into stock amp. Also wht to do w. The old stock wires wich have slots 4 and 5 still in contact with harnace B and slots 7, 3 & 4 in contact with harnace C? A re ply would be greatly appreciated about now thnkyuu!

Vulkan132

What if you wire the aftermarket soeaker wire into the plug and plug it back into the amp. What would that do?

AWehland88

I didn't have any aftermarket speakers to hook up, so I'm not sure how it would work trying to plug those into the factory amp.

Prinny

Any more pictures of install?

AWehland88

Unfortunately no, no more pictures of install.

phoenixnsx

I replaced the factory stereo in my 1998 ES300 this weekend, and I did NOT have to bypass the factory amplifier. No messing with the factory amplifier was necessary! The only splicing I had to do was on the aftermarket stereo connector and the Metra wiring harness. I did not go into the glove box or cut any stock vehicle wires.

I documented the process here: http://imgur.com/a/rDJW3 (also in attached PDF)

My stock stereo looks nothing like the picture in the OP, but I can verify that the sound from my new stereo plays through the factory amp to the factory speakers.

Let me know if there are any questions.

Edit: Just wanted to mention that if I had it to do over again, I would choose the over the Metra 70-8112 as the former has an orange illumination wire that the latter lacks, as mentioned in this amazon review:

Prinny

Wow, did you put that pdf together? If so props to you! Very detailed and easy to follow. I know a friend that has been wanting to change his out. I'll definitely be sending that his way.

phoenixnsx

Yes, I''m glad someone else finds it useful.

jaredmac11

Hey, I did a similar install as you except I used the BHA8112 harness. The head unit powers on but will not produce sound. It was a formerly working HU that I pulled from my totaled vehicle to use on my 97 ES300.

What could cause this? I plugged in the factory stereo again and it works, so my fears of blowing the amp were quelled. Im assuming something must be wrong with my wiring or the RCA connectors? Any tests I can perform? I did not use the BHA8112's orange, orange/black, or blue wires since none of these had a 'like' wire for the headunit's harness.

phoenixnsx

Sorry for the late response. I ended up replacing my wiring harness with the BHA8112, and everything works just fine (including auto-dimming) in my car. Maybe your aftermarket stereo was damaged somehow from your previous car's accident? I'd also double check all the harness wiring, it's easy to get something incorrectly wired by mistake. Good luck.

jaredmac11

Thanks! It was the brown wire. I thought this would enable the mute functionality to the speakers when a call was active, but it ended up muting the entire system. Once I disconnected that, it was all good.

McMuffin

Sorry for the old thread bump, but I'm looking to upgrade my head unit as well in my 1997 ES300. I have 2 questions.

1. If I just want to upgrade the head unit and have the rest of the factory system work, will the method in the original post work? OP mentioned something about bypassing the factory amp, but wouldnt this mean that the subwoofer isn't working anymore?

2. If I want to put in aftermarket HU/Speakers/Amp but still want to keep the factory subwoofer working, how would I go about doing this? Any ideas?

Thanks

whooodat

iTrader: (4)

McMuffin-

I had a JVC double din stereo put in my wife 98 ES300 several years ago and I believe that I bought a connector that allows you to connect the subwoofer (purchased from Best Buy, was around $40 ..... I think). Once they did the install of the new headunit I only had sound coming from the tweeters and door speakers, none from the subwoofer. I had to go back and complain and they added the part and everythings been good since. Note: They installed new headunit and tied them into the stock Nakamichi speakers.

bchboyfm82

just bought a new head unit for my 01 es. and although everything looks dead on exact in these pictures compared to my car(cars harness/amp behind glove box) it says the harness isnt compatible with my car when i click on the link and am sent to amazon. and yes i do have another car but my 01 es is selected as my car while i browse. am i good to buy this still or is there a difference between the model years? thanks for any help im looking to do this asap as i only get 1 day off in the week.