Ls400 Audio System

[traderlou76]

I bought a 95 ls400 recently and i was driving it this weekend and the stereo sounded great. I shut it off and got out and when i started it back up there was nothing. Stereo turns on fine but no sound and the fuses all look good and i did check power to the amp and it was hot. Does anyone have any suggestions? I did see something about a phone but mine doesnt have one. Funny thing that it never even acted weird before it stopped, it was like someone muted the radio. Thanks with any help i can get. it is a nakamichi 50160 amp.

[1990LS400]

If you saw a post about a defective phone ECU in the trunk causing an LS400 audio system to go into mute mode, it might have been one of my posts since I've mentioned it a number of times. I got a friends 99 LS400 Nakamichi working again by disconnecting his defective phone ECU.

Be sure to verify that both the radio 1 and radio 2 fuses are good. One is in the engine compartment and the other under the dash on the drivers side.

One way to see if your amp is good is to try it in another 95-97 LS400 with Nakamichi. Know anyone who has one? That's how I tested my 00 LS400 Nak amplifier when the right side channel went out four or five(?) years ago. I pulled out my Nak amplifier, laid it on the rear floor of my friends 99 LS400 and plugged his amplifier cables into my amp. My amp worked fine so I sent my radio head unit to http://www.carstereohelp.com/ in Florida for repair. A wire at the balance control in the head unit was loose.

My understanding is the that the interiors of 95 through 2000 LS400's are basically the same. If so, you should be able to remove your amp without removing the front passenger seat. It was fairly easy to do in my 00 LS although I needed someone else to press done on the metal tabs on the front of the amplifier when reinstalling it so I could slide the tabs into the slots under the front of the passenger seat.

In theory it's possible that a grounded telephone mute is still causing your radio to mute but I think it is unlikely. If you haven't owned your car since new, check under the removable floor on the right side of the trunk to verify there is no phone ECU. On cars without a dealer installed Lexus phone, the phone connectors in the trunk containing the telephone mute are attached to the bottom of the tool kit receptacle where it is doubtful they could get wet and short out.

I was told by Car Stereo Repair several years ago that it was getting difficult for them to repair Lexus Nakamichi due to a lack of parts availability. Nakamichi when bankrupt a long time ago and the current Nakamichi is Nakamichi in name only.

If you have to pull the head unit, it is not difficult. Remove the center air vent, pry out the console wood panel and you will see the four 10 mm bolts holding the head unit in place - two top, two bottom. Be sure to cover the console area with a heavy towel or similar so you don't scratch it when you pull the head unit.

[traderlou76]

If you saw a post about a defective phone ECU in the trunk causing an LS400 audio system to go into mute mode, it might have been one of my posts since I've mentioned it a number of times. I got a friends 99 LS400 Nakamichi working again by disconnecting his defective phone ECU.

Be sure to verify that both the radio 1 and radio 2 fuses are good. One is in the engine compartment and the other under the dash on the drivers side.

One way to see if your amp is good is to try it in another 95-97 LS400 with Nakamichi. Know anyone who has one? That's how I tested my 00 LS400 Nak amplifier when the right side channel went out four or five(?) years ago. I pulled out my Nak amplifier, laid it on the rear floor of my friends 99 LS400 and plugged his amplifier cables into my amp. My amp worked fine so I sent my radio head unit to http://www.carstereohelp.com/ in Florida for repair. A wire at the balance control in the head unit was loose.

My understanding is the that the interiors of 95 through 2000 LS400's are basically the same. If so, you should be able to remove your amp without removing the front passenger seat. It was fairly easy to do in my 00 LS although I needed someone else to press done on the metal tabs on the front of the amplifier when reinstalling it so I could slide the tabs into the slots under the front of the passenger seat.

In theory it's possible that a grounded telephone mute is still causing your radio to mute but I think it is unlikely. If you haven't owned your car since new, check under the removable floor on the right side of the trunk to verify there is no phone ECU. On cars without a dealer installed Lexus phone, the phone connectors in the trunk containing the telephone mute are attached to the bottom of the tool kit receptacle where it is doubtful they could get wet and short out.

I was told by Car Stereo Repair several years ago that it was getting difficult for them to repair Lexus Nakamichi due to a lack of parts availability. Nakamichi when bankrupt a long time ago and the current Nakamichi is Nakamichi in name only.

If you have to pull the head unit, it is not difficult. Remove the center air vent, pry out the console wood panel and you will see the four 10 mm bolts holding the head unit in place - two top, two bottom. Be sure to cover the console area with a heavy towel or similar so you don't scratch it when you pull the head unit.

thanks alot for the reply. ok i pulled the amp out. Is there a way to test the amp besides putting in amother car, i dont know one here. thanks

[1990LS400]

Are you in a populated area of Washington state in out the boonies? Have you had any contact with a repair shop that works on Lexus cars - maybe they could put you in touch with someone who has a 95-97 LS400 with Nakamichi. I don't know how common Nakamichi is on the 95-97 LS400 but they are fairly common on the 98-00 LS400 where I live. I don't know of another way to test your amp unless you can find a professional who could do it. I suppose you could call the car stereo repair company in Florida - website was given above - to see if they could test it and maybe fix it if it is broken but it sure would be easier if you could find another car to plug you amp into.

[pilotinparadise]

I just bought a 97 LS400 with the Nak stereo. The seller told me the audio just dropped dead a few weeks ago. I can cycle through the FM/AM, Cassette, CD, etc and the display shows correct info (track no, or station ID, etc). There is a very faint audio output from the speakers. Is there any chance my amp is fine, but the phone has set the system to mute?

If so, how do I confirm this, and what is the remedy? I have the trunk deck pulled back and have easy access to all the phone connections.

Please help. I miss having a stereo in the car!

Marty from Muggy, boiling, rainy, wonderful Palm Beach, Florida!

[1990LS400]

I just bought a 97 LS400 with the Nak stereo. The seller told me the audio just dropped dead a few weeks ago. I can cycle through the FM/AM, Cassette, CD, etc and the display shows correct info (track no, or station ID, etc). There is a very faint audio output from the speakers. Is there any chance my amp is fine, but the phone has set the system to mute?

If so, how do I confirm this, and what is the remedy? I have the trunk deck pulled back and have easy access to all the phone connections.

Please help. I miss having a stereo in the car!

Marty from Muggy, boiling, rainy, wonderful Palm Beach, Florida!

Unplug all the phone connectors in the trunk from the phone ECU. If there are two matching connectors - one male, one female - plug them together to complete a circuit. Being barely able to hear the audio can be a sign of a defective phone ECU as it was in a friends 1999 LS400 with Nakamichi. I use one of the OEM mute pins on my 2000 LS400 (also with Nakamichi) to automatically mute my radio during an incoming or outgoing phone call with my aftermarket phone kit but I can still barely hear the radio while it is muted.. Your 97 LS400 has an audio system mute pin in a connector under the center console and in the large phone ECU connectors in the trunk either of which can be used with an aftermarket (e.g. Bluetooth) phone kit.

Report back to us and tell us how it went.

[pilotinparadise]

Jim,

Thanks for the quick follow up. A few minutes after I sent my post of woe, I went back to the trunk. There are a handful of connectors for the phone's ECU, all of which I pulled. Two or three of the pins were heavily corroded, including a black wire pin.

Next step, into the drivers seat, powered up the car, turned on the stereo and ... nothing.

I scratched my head, wondered if I needed to either ground or 'unground' a wire. Got a bug up my butt, and pulled fuse #15 (radio 2). I'd already checked it yesterday, but hoped it was burnt. No luck.

I restored the fuse, turned the car on, and just about blew the doors off the car in the driveway next to me.

I now have a perfectly working Nakamichi stereo. All functions, tape, FM/AM, and CD work fine.

I suspect pulling the fuse and replacing it reset the 'Mute' status on the head unit. I did not connect any of the male/female clips in the ECU to each other. Just left them hanging. I'll give the lot a proper burial tomorrow.

Hopefully this info will help others with a similar issue.

Marty from Muggy, boiling, rainy, wonderful Palm Beach, Florida!

[1990LS400]

Actually, I suspect that pulling the connectors from your phone ECU is what fixed the issue. In my friend's 99 LS400 with Nakamichi, the radio fuse in the engine compartment fuse box kept blowing until we unplugged the phone ECU. His Nakamichi audio was restored by unplugging the phone connectors from the ECU.

A defective phone ECU causing the audio system to go into permanent mute is a very common problem on the LS400. I've gone through this routine with lots of other LS400 owners.

If two of the phone ECU connectors plug into each other then plug them together after removing any corrosion from the pins. Tuck the connectors up and out of the way so they don't get damp. On late model LS400's without dealer installed Lexus phones the phone connectors in the trunk are attached to a plastic bracket attached to the tool kit receptacle.

Maybe throw the phone ECU away but don't cut or remove any of the phone wires or connectors. If you still have a phone handset/cradle, do some minor console disassembly and unplug the handset/cradle. Again ... don't chop wires!

[dcfish]

If you need parts/components, Let me know. I probably have what you need

[DanteMc]

Knocking dust off this.... I have a 95 LS400 with factory phone and it is constantly making the button tone. I have seen posts saying the ECU needs to unplugged and it is located on the right and others say left. I pulled back the panels in the trunk driver's side. Found out not to unplug the red box. It does tail lights. There are connections at the base of the antenna. Is that the phone ECU?

Those trunk panels are hard to manipulate. Anyone have any far back photos showing where the ECU is specifically located?

Radio is broken so bare minimum of disabling the speaker is a very favorable option.

Thanks!

[1990LS400]

Look at post #2 in this thread which I provided two years ago. The phone ECU is on the right side of the trunk beneath the easily removable small false floor panel exposed when the carpet mat is removed - very easy to access.

Unplug all the connectors from the phone ECU, plug the two large ones not connected to the phone ECU together and tuck them up out of the way so that they do not dangle in the well and get damp. If your car didn't have a dealer installed phone, the two large connectors on the "car side" of the harness would be attached to a plastic bracket attached to the bottom of the tool box housing. I think it's best to completely remove the phone ECU so that it is clear which cables are on the car harness side and which are on the phone ECU side. The phone ECU has no value.

That "should" get rid of your beep.

If it doesn't, unplug the phone handset cradle. This requires removing the console box under the armrest which on my 2000 LS400 is held in place by only three screws - two at the front behind a little hidden pop-off panel and one at the back of the box under the pop-off vent cover. I think 1997 was the first year that had a power outlet in the console box so I don't think you have to remove the console wood panel and cup holder. If you do, it's easy to pry out the console wood with a non-scarring trim removal tool. Only four screws hold the cup holder in place - accessible after the console wood is removed.

The phone handset cradle is plugged into connectors under that center vent you see when the console box is exposed. Unplug the connectors - don't cut any wires. If you want to remove handset cradle, used something like a thin blade putty knife to pry the black insert out of the upper console tray. Work your way around the edges and pry gently but firmly. The holes left in the console tray after removing the handset cradle can be patched. I covered them with electrical tape on the underside of the tray insert. The console insert snaps into place.

Here is a photo of the phone ECU in a 98-00 LS400 - your's probably looks very similar unless you have the rare portable handset. Also attached is a photo showing lifting the console box out of my 2000 LS400.

The photos are from 10 years ago but I happened to have the console disassembled yesterday during the replacement of my failing OEM Nakamichi with a modern screen based double-din Kenwood.

[DanteMc]

Thanks!!! This spelling this out nicely:

"The phone ECU is on the right side of the trunk beneath the easily removable small false floor panel exposed when the carpet mat is removed"

Trying to pull back on those side panels is a pain. Getting to the floor panel was far easier!

I disconnected the two connectors coming out of the wiring harness from the front of the car and attached together. Started the car twice and no bleeping beep. :) Yeah!!

I uploaded some photos with labeling to my gallery. They don't show up when I try to attach. I will try and attach again tomorrow for future reference.

[95LexusAl]

   Hi,I just joined L.O.C.I have a '95 LS400,223K miles with the Pioneer radio controller,part# 86120-50360.The LCD display went black a while back.If I knew a company,address,and phone#,I could call them to see if the LCD display could be replaced.With in the past year.I had installed two other radio's(part#'s 86120-50361) in it @ a Toyota dealership and neither worked properly.Yea,I know,it cost a bundle for nothing.

   Before the 2nd one was installed,I called the Lexus dealership and asked them would the 50361 work in my '95.I gave them my original part#.The parts dept. employee told me it would work in my '95.He said the 50360,61,and 62 are interchangeable.I now know for sure that the part# has to match in order for the replacement to work right provided that the radio was working good before being pulled.On the two radios that were installed,the LCD display did not light up and if they did,they would be very faint.So the parts guy is wrong.Also,the antenna mast doesn't work anymore and is too costly to replace it.I did replace it once with another OEM part off Ebay.But it only lasted for a couple years.So I won't replace it again.I'll just pull the antenna up when needed.Only takes a few seconds vs a cost of probably over $500 from the dealer.

   I've owned this LS400 for over 18 years since May 26th 1998.I've never kept a car that long.But I've been so fortunate with the reliability of this '95.That's how good they are with the proper upkeep.I can't complain very much since the car has been so good all these years.There are some other minor issues to be fixed but they aren't related to the audio system.I also did repair the sub woofer a while back.Not too difficult once removed.It just takes patience.

   I also bought a silver '99 LS400 in May 2014 and the stereo system is ok for the time being.There maybe a few sellers on Ebay that can fix the '95 radio.But I don't know if I can trust their work,no matter what their feedback says.I also recently had it repainted due to fading on the top front to back.I really like the Moonstone 6NO color code on mine.

   If anyone can lead me in the right direction,I sure would appreciate it.Thanks and glad to be a new member.