1996 LS400 FITTING AN AFTERMARKET DOUBLE DIN STEREO

Because my head unit had ceased to function I decided to upgrade to a modern Pioneer 2 DIN unit, which gives a more up to date unit and includes AUX and USB inputs, together with the ability to be connected to a reversing camera. However, the CD changer became redundant because the new head unit does not have the facility to operate it.

I should stress that I am not an auto electrician, just an amateur who likes fiddling with cars, which is why it took me a long time to get to the point of commitment. As such, I offer no guarantees that the following will work on your particular car, so feel free to double check anything or everything. That said, the stereo worked as it should first time, so I must have done something right!

I spent may hours poring over wiring diagrams and reading various forum topics on the internet and the following is a distillation of what I found, mostly from the US. I did discover, however, that the wiring colours for the US market can be different to Europe, so cannot necessarily be relied on for accurate identification.

I found several methods of wiring in the new unit, but many involved splicing wires at the amplifier connectors, running new wires to the amplifier or bypassing it altogether, none of which seemed an ideal solution. The way I did it utilises the existing speaker/woofer wiring and amplifier, which is what I was aiming for.

In this case I bought a used Pioneer MVH-A200VBT (with instructions – important!), which I am very pleased with, especially the convenience of a touchscreen, but presumably almost any 2 DIN head unit should work.

Once I had figured out how to replace Lexus's unique connectors with ISO connectors I bought the stereo and ordered the following installation kit from the US, via eBay. It doesn't seem to be available anywhere else.

Metra 95-8153 Double DIN installation kit for 1995-2000 Lexus LS vehicles.

The colour and texture of the plastic are slightly different to the climate control fascia, but acceptable. The sides are also plastic, and appear flimsy, but are perfectly adequate for the job, once everything is screwed together.

This is the wiring diagram I found most useful:

And these are my own schematics for the white and grey connectors on the back of the stereo, which helped me understand which wires to connect, and which can be ignored:

The blue connector can be disregarded because it is for the CD changer, which became redundant.

I make reference to ISO connectors because these appear to be the most common ones used and my head unit came with an adapter from the 16 pin connector used by Pioneer.

I used a six way male/female connector for the power wires and two four way male/female connectors for the speakers, i.e. separate ones for left and right channels, mainly because they are grouped and shielded as left and right. I reversed one side so that the speaker connectors could not be connected to the wrong side. On reflection it might have been easier, and neater, to get the ISO connectors in kit form and attach them directly to the harness, thus doing away with an extra set of connectors.

I would mention the following points to bear in mind:

• The woofer on the rear parcel shelf is driven from the amplifier only. There is no connection from the head unit.

• On the grey connector there were three wires for the antenna, marked ANT+ (12), ANTA (4) and ANTB (13). I spliced these together and the aerial is now activated when the unit is switched on. On the original unit the aerial only worked when the radio was selected, and did a little bob when the preselected channel was changed, which is why I assumed there are three wires instead of just one.

• Also on the grey connector there are three earth wires, GND (14), GND1 (5) and SGND3 (9) which need to be earthed.

• Again on the grey connector I ignored pin 8 because I couldn't find out what it was for. I also ignored AP+ and AP- because they relate to the redundant CD changer.

• On the white connector there are two earth wires , SGND1 (3) and SGND2 (2), both of which need to be spliced into an existing earth, or a new one created. SGND means Speaker Ground.

• Also on the white connector I ignored Beep (8), Mute (9) and Tel Mute (10).

• Again on the white connector I connected AMP+ (11) to the antenna power lead. In my case Pioneer conveniently provided a spliced wire that could be used, so that both the aerial and amplifier are powered when the unit is switched on.

• I labelled all the wires, both on the car harness and the ISO connectors, before cutting any wires.

Here is a summary of the connections I made:

GREY CONNECTOR (reading from top left to right)

1. +B - blue/yellow – battery. Disconnect battery first!

2. Not used

3. Green – interior lighting. This is not shown on the wiring diagram I used though.

4. ANTA – blue/red – antenna. Splice with 12 and 13

5. GND1 – brown/black – earth. Splice with 9 and 14.

6. ACC – grey – accessory ignition

7. Not used

8. White/green. Purpose unknown. Ignored.

9. SGND3 – brown – earth. Splice with 5 and 14.

10. AP+ - white – CD changer. Ignored.

11. AP- - black – CD changer. Ignored.

12. ANT+ - black/brown – antenna. Splice with 4 and 13.

13. ANTB – white/red – antenna. Splice with 4 and 12.

14. GND – brown – earth. Splice with 5 and 9.

WHITE CONNECTOR (reading from top left to right)

1. FR+ - white - front right speaker positive

2. FL+ - black – front left speaker positive

3. SGND1 – grey – earth. Splice with 12

4. RR+ - green – rear right speaker positive

5. RL+ - red – rear left speaker positive

6. FR- - red – front right speaker negative

7. FL- - white – front left speaker negative

8. BEEP – black. Ignored

9. MUTE – blue/white. Ignored

10. TEL MUTE – grey/black. Ignored

11. AMP+ - pink/blue - Amplifier. This I connected the the antenna feed.

12. SGND2 – brown/red – earth. Splice with 3

13. RR- - yellow – rear right speaker negative

14. RL- - green – rear left speaker negative

Space is a little restricted behind the centre console to cut the wires and crimp on the new terminals, but I found it helped a bit to remove some of the outer sleeve and foam from the harness. I left the shielding for the speaker wiring intact though.

The Metra fascia conversion kit fitted perfectly and I found there was no need for the bezel that came with the stereo because the aperture was just the right size, the stereo unit being fitted from the rear of the fascia. A fitting cage was not required either because the stereo attaches to the side brackets of the kit, using the screws that came with the stereo.

On my stereo the AUX and USB sockets are on the back of the unit, so I bought an appropriate male/female lead with a flush socket so that it could be mounted in a blanking plate in the dashboard, just to the left of the steering column. Whilst everything was dismantled I included a twin USB charger socket, taking a feed from the lighter socket in the centre console.

eBay item "WILLITZER USB 3.0 and HDMI (sic) Male to Female Round Car Flush Mount Cable Extension".

The saga is also shown in this topic: