1996 LS400 AUDIO UPGRADE OPTIONS

[BigBoomer]

15 hours ago, Howplum said:

Am I barking up the wrong tree?

Very likely. Woof <LOL>
The switch is probably a momentary one that then causes a solid-state relay to latch elsewhere in the circuitry.
It is a common config for audio equipment as mechanical switches wear and fail.
 

[Howplum]

Thanks George, that's useful to know. I'll fit the replacement capacitor when it arrives and see what happens.

Another option is to completely update the head unit and fit a double din unit of some sort, although connecting it to the existing harness, especially the amplifier, might be challenging. No doubt I will lose the CD changer facility though.

https://thebassbin.co.uk/product/autoleads-dfp-25-03-lexus-ls400-double-din-fascia-panel-adaptor/

 

[Howplum]

Replacement capacitor fitted but the unit is still dead, so time for a rethink.

I could get yet another used unit, but that would also be 25 years old, so could also potentially have issues in the future.

All I use it for is listening to the radio, preferably via 4G or DAB+, or my own music, which is on both iPod or USB stick. This is why I was trying to add an auxiliary socket. Telephone connectivity is not important.

The idea of a 2 din unit, possibly with a touch screen, appeals, especially if Google Maps can be displayed from my phone. Perhaps best to avoid the unbranded £45 ones on eBay though!

I think the makes to look at are Pioneer, JVC, Sony, Kenwood and Alpine.

Something to research over the festive season.

[BigBoomer]

Make sure to check the clearance behind as some of the 2xDIN units can be quite deep.
A friend has a Kenwood DMX5020DABS and he says it's great but ££££.
Supplied and fitted to his 2002 Honda Legend it cost a little over £500 about 6 months ago.

[Howplum]

3 hours ago, BigBoomer said:

Make sure to check the clearance behind as some of the 2xDIN units can be quite deep.

Hopefully no deeper than the existing unit. I would probably choose "mechless" anyway, which tend to take up less room.

[Howplum]

I have now ordered a Metra 95-8153 double din adaptor from the US because it doesn't seem to be available in the UK, despite the website I found stating they had 100 in stock!

[Howplum]

I have now bought a used 2 DIN Pioneer touchscreen head unit off eBay, model MVH-A200VBT:

https://www.caraudiocentre.co.uk/product_m-pioneer-mvh-a200vbt_p-40737.htm

Whilst awaiting delivery, I'm trying to figure out the wiring and how best to connect the existing harness to the ISO connectors on the new unit. No proprietary adaptor harness is available so I therefore have several questions before embarking on yet another learning curve!

1. There are currently three wires that connect the radio/player to the antenna and its relay, marked ANT+, ANTA and ANTB. The antenna is designed to only rise when the radio (tuner) is on, but since the replacement unit only has the one wire (blue) my quandary is to which connection to use. I read on a US forum that connecting to all three seems to work, but is that right? On other setups the antenna usually only rises when the unit is switched on, regardless of which function is being used, although perhaps a separate switch could be fitted if desired. This the wiring diagram from the US Repair Manual I have:

2. Should I include the existing amplifier? This is less work from a splicing point of view because it utilises the existing wiring. However, my concern is that the new head unit produces 50W for each of the 4 channels, but I can find no information on the output of the original system*, so I wonder if the speakers can handle a more powerful setup, if that is indeed the case. So far I have found that having the volume at 30% or less is perfectly adequate, because the car is so quiet.

*After some more digging it seems the outputs of the amplifier are 40W front, 30W rear and 55W woofer.

On a US forum mention is made of the Nakamichi door speakers being rated at 20W/40W, but that may be a red herring.

3. There is currently a wire marked AMP+ from the head unit to the amplifier, but I'm not sure what it does. Does it just provide power to the amplifier when the head unit is switched on?

4. The woofer on the rear shelf receives its signal from the amplifier only, not the head unit, so if I opt to bypass the amplifier I will need to use the woofer connections on the back of the new head unit.

5. There are three connections on the existing Pioneer unit marked SGRD1, SGRD2 and SGRD3 which apparently are Speaker ground wires, so presumably/hopefully these can be spliced together. 

These are my schematics of the existing radio/player connectors:

 

Any advice or observations would be appreciated.

[Howplum]

The replacement head unit has arrived, and apparently the 2 DIN adaptor should be here next week.

In the meantime I have been studying the wiring and noticed there is a dedicated RCA input for a reversing camera, which must be better than my present wireless version. There is also a wire to be connected to the reversing light circuit so that the screen automatically comes on when reverse is selected, but it would be a lot easier to splice into the appropriate wire from the reversing light switch under the centre console, although it's location is not immediately obvious without some serious dismantling of the gear selector assembly. I've had a look on my electronic repair manual but there is no mention of the switch that I can find.

Because the new head unit has both USB and 3.5mm inputs I decided the modify the centre console by removing the ashtray assembly and fabricating a plastic panel, into which I fitted a charger socket, twin USB charger socket and a dedicated USB/3.5mm socket for the stereo - i hope it works when it is all connected up.

I've also been labelling the wiring so that I make up a couple of ISO adaptors:

 

[runsgrateasanut]

Nice idea for the Ashtray.  I recently bought the below which was the last available and saves a lot of hassle (so I believe) in installing a Single Din on my GS300. Instead of rerouting the Cable from the Amplifier and splicing etc  I will only need to disconnect it and plug in this extension lead which then routes back to the rear of the unit and connects to a large double block which is prewired to a smaller Double block which fits into the Sony Xplod. Job done - well when I get around to it.!

https://www.ebay.co.uk/itm/273860080043

[Howplum]

Thanks. Unfortunately there is no adaptor harness available for the LS400, either here or the US, which is why I've resorted to making my own. Hopefully I will know soon if I am successfulor not!

[Howplum]

Thanks. Unfortunately there is no adaptor harness available for the LS400, either here or the US, which is why I've resorted to making my own. Hopefully I will know soon if I am successfulor not!

[Howplum]

Success! The head unit is all connected and working, so I will do a tutorial on the wiring in due course. Hopefully it will help somebody in the future. The only slight snag I have is that the woofer isn't working, but I don't know if it was working before, so investigation is needed. It is connected directly to the amplifier, so hopefully isn't related to anything I have done. If necessary there are woofer connectors on the back of the head unit I could use.

Hopefully the mounting kit will arrive this week.

[Howplum]

The mounting kit arrived today so I wasted no time in installing the head unit. At the same time I decided the sockets in the ashtray space looked a bit clunky, so I relocated them to the small blanking panel to the left of the steering column, which looks neater.

Reviewers of the mounting kit said the texture and colour of the kit is slightly different to the original, but in the grand scheme of things I can live with that.

I must say the Pioneer unit gives very good sound and is easy to use, so hopefully it will last for several years.

In the end I found the woofer was working after all, it's just that I couldn't hear it properly.

  

The next job is to fit the reversing camera, which hopefully won't be quite so involved!

 

[MJB18]

Well done, that's very impressive Howard!

[Howplum]

Thanks Mick. I must say I was surprised, and relieved, when it worked first time.

[Razor61]

13 hours ago, MJB18 said:

Well done, that's very impressive Howard!

I second that, the usb stuff crafted into the blanking plate on the dash looks great.

[Howplum]

Thanks Paul. Here's a close up. The double USB socket is spliced into the wires for the lighter socket in the centre console.

[Howplum]

I have now done a tutorial, which hopefully will prove useful to anyone embarking on such a project:

 

[Howplum]

Having taken the car out for a run yesterday I noticed that there is a slight whine which varies with engine speed, so is probably related to the alternator in some way. It appears to disappear almost as soon as the car is moving, but that is only because it is covered by the general wind and road noise. I did notice that it is present even when the stereo is on mute, so is still being transmitted by the speakers. Having done a quick bit of research it looks as though it might be a earthing (grounding) issue, so I firstly need to check that all the earthing wires are present and correct. Perhaps the earthing circuit is struggling because I spliced multiple wires together.

The next step might be to install a ground loop isolator.

Any thoughts or experiences?

[BigBoomer]

Ground loop isolator may help, but sometimes all it needs is a suppressor on the +12V wire that supplies the radio.
You do need a really good earth for radios. I have often run a dedicated earth lead to the Battery -ve post when fitting my Ham radios to the car, just to get a 100% good earth.
 

[Howplum]

Thanks George. I'll give that a try. Suppressors seem to come in various ratings from 3 to 30 amps. Do you happen to know if bigger is necessarily better, or do I match it to the rating of the fuse supplying the stereo?

I found this information, which could be useful:

"Speaker Whine From Alternators

One common cause of speaker whine comes from the vehicle's alternator. If the noise changes in pitch or intensity when the engine RPM changes, it's probably some type of engine noise, and interference from the alternator output is a likely source.

The issue is that noise from the alternator is getting into the head unit via the power cables. You can deal with the problem in one of two ways:

• Install a noise filter between the alternator and the Battery.
• Install an inline noise filter in the head unit power cable.

In either case, the alternator will still generate noise but it won't be able to get into the head unit and cause the speakers to whine."

 

[BigBoomer]

Just match the rating of the fuse.
The bigger ones are the same, but more expensive due to handling higher currents.
If they are all the same price, then get the biggest rating.

[Howplum]

Thank you.

[Howplum]

Noise filter now fitted and the whine has disappeared, so now all sorted.

[hockeyedwards]

Fantastic modifications, very jealous of the USB locations.

Also loving the guide for the aftermarket stereo, will be copying it all down for sure when the time comes!

I will also be opting for a reversing camera as I didn't want to ruin a rear bumper. What model are you using/ going to use?