CubFan22

Well ole Betsy is showing her age again. Stereo powers up and appears to be working but no sound. I press the Mute button repeatedly and nothing seems to happen. I cannot tell if the mute is on or off. From reading other threads, there is amp located under the rear passenger seat. I live in the Caribbean and the nearest stereo mechanic is an hour away so I would like to try and DIY. Of course, I have no experience troubleshooting car audio. But I actually would like to take this opportunity to learn. Unemployed right now and have endless time on my hands. What tools and diagrams would I need and how would I actually test the amp and work my way back to the stereo? From experience what is the probability I need a new receiver? Should I start searching for one?

Hopefully I will have some music without buying a new receiver.

CubFan22

I have a 1999 RX 300

maxSteel

Cant post anything, it will be deleted.
Do a web search for 1999 rx300 radio wiring diagram, you will find one

thomas1

Here is a thread with the info you need...
https://www.clublexus.com/forums/rx-...-volume-2.html

CubFan22

Thank you guys. Went on a hunt for the amp today, Popped the rear hatch open and lifted up the carpet where it meats the rear seats and found this retractable door bolted down. Think I see the amp through one of the holes. There is another screw under the carpet on the back of the seat. Looks like you have to pop the round plastic clasps to access this screw.

Trying to insert a picture I have on my hard drive of this door, but its asked me for a URL. How do I upload a pic from my harddrive?

maxSteel

use 'Post Reply' not 'post quick reply'
in 'additional options', press 'manage attachments'

99rx

iTrader: (6)

If i may add, this may be a security system issue. Do the dome lights and interior lights illuminate when the drivers door is open?

CubFan22

I believe the lights do come one. I know the interior lights on the door come one when the door is open, but I am not sure if the dome light comes on. I will check today. My gut feeling is the amp is fried. This car sits in the sun sometimes with the windows up in 100 degree weather.
Here is a photo of the latch/door behind the rears seats: Going to open her up today and see if I can test the amp.

CubFan22

I have not removed the amp yet, perhaps its best tested while still installed?

Kansas

Consider checking in the trunk to make sure that the mute pin/wire originally meant for the phone system isn't getting continuously grounded by water/corrosion. If your car has/ever had one of the Lexus phone system, this is even more likely a possible cause of permanent radio mute.

Here is an old thread with information about the telephone mute connection in the trunk of the gen 1 RX: https://www.clublexus.com/forums/rx-...led-nokia.html

A friend didn't have sound in his 99 LS400 for a long time ... maybe six months. I disconnected the old unused phone ECU in his trunk and, voila, his radio came to life.

CubFan22

Kansas, thank you. I notice there is a plastic junction box behind the jack in the trunk (passenger side). There is also the same box on the drivers side. Is the phone ECU inside this junction box behind the jack?

Kansas

If your RX has a phone ECU it is on the right side of the trunk. Whether it has a phone ECU or not, there is or at least should be a phone connector on the right side of the trunk that has a mute pin.

CubFan22

Thanks Kansas. I cannot seem to find a Phone ECU in the trunk.

But I believe I figured out the problem,

WATER DAMAGE TO MY AMPLIFIER IN THE TRUNK ITS LOOKS FRIED!
First, it took me almost an hour to remove the amp. I ended up having to remove over
twenty plastic and metal screws. Seriously. Neve was able to remove the black bar as
it appears you have to remove pieces of both sides of the trunk to remove the bar.
I was able to finally get enough room under the bar to remove the 3 screws holding the amp bracket. When I opened up the amp, I notices some rust on the inside. Then I remember how I 5 gallon water bottle I had in the back of the trunk leaked a few months ago. At about the time the stereo stopped working. In fact there is giant water stain on the carpet in the trunk. Great design job on the black bar and the placement of the amp. NOT! I will post pictures later. On me way to have the amp tested by an audio tech just to make sure its fried.

Thanks all.

CubFan22

I am beginning to wonder if removing all the screws was neccessary to remove. Wont be surprised if I wasted alot of time. haha. --Me

CubFan22

Got really lucky on ebay was able to buy used amp that works for $35 as the only bidder.