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My 2004 Sc 430 is having radio and navigation problems.
My radio is receiving power and can change stations, can play cd's . Although it does not produce any sound from speakers, even dead air noise.
AAA had someone form Premier auto come to my house and they took out the navigation dvd ubit the atennea booster and the ML Amplifier.
They bench tested it and said everything was fine. when the tech came back to ire-install, the tech told and showed me that the radio has power, the navigation unit in the trunk has power. the problem seems to be that the radio is not sending power to the amplifier or the navigation screen in the car.
he did show me that the amp can turn on by jumping the wires but he cold not figure out why the amp was not getting power from the radio. he did check all the fuses in all the areas of the car but he cold not find where the break was in power from the radio to the amplifier.
i have the wiring diagrams for the radio and amp but the hard part is where are all the connections being made. i diagram only show the radio, amp , speakers and how the wires all connect to each other.
What i reall need to know is the diagram of wiring run from the radio to the amplifier in the trunk.
Exactly where do the wire's run in the car from the radio to amplifier. if any one has a drawing or photos of where each connection is made that would be great.
as you can see on the lexus supplies images it shows the wiring but it does not say where in the car any of the connectors are located.
I know it will be just one wire that somehow got un pluggeg.
again i know that the radio is getting power but it is not putting out any power suginal to the ML amp in trunk..
You’re asking for 10-15 pages of diagrams. The radio also has a self diagnostic but that has several pages of codes.
Also I am assuming, since you did not say, you’ve adjusted the volume **** and changed the switches, mute,mode,up down on the streering wheel pad? Did the AAA guy look in all four location for fuses? This system is rather complex, using a AVC-LAN to communicate not just wire from the radio to the amp to the speakers.
Iam sorry , I did not mean to upset you or anyone. i have spent many hours on this. and just trying to figure out how to get sound from my radio or get my navigation screen to turn on. i do know that the radio and navigation screen are connectd in some way. if i can just find the path of the main harness from battery to the ML amp in trunk i might becable to find the place its disconnected and reconnect it.
al now going to go check out the radio diagnostic you posted. i did not know about that. i thought the only diagnostic was the one on the navigation screen that wont turn on even for a second.
Yes i did check all the *****. i have adjusted the volume **** and changed the switches, mute,mode,up down on the strearing wheel pad the volume will not go up or down, the fader or balance does not work at all . it will let me select cd and play cd's but no sound. yes the tech did check all the fuses in all the locations. he said they were all good and there must be a connection that got disconnected.
his final statement was that _ "No power to main harness of amp from the battery 25am source."
Thank you again ill let you know what happens when i get back from the radio diagnostic.
Not upset whatsoever. Just stating you’re asking for a lot of data. I’m curious, you’ve taken the trunk interior garnish apart. It’s the only way to get to the amplifier and navigation DVD player. Is the correct?
also, it’s more than just a “wire”. Lexus uses a complex integrated audio visual comm local area network or AVC-LAN as part of its multiplex communication system in the car that is daisy chained through several ECUs.
Yes i have taken all trunk trim out. that is how the tech from premier radio took out the amp, attena modulator and the dvd navigation drive.
they bench tested it at the workshop and ran it for 24 hours . they said ai all worked perfect.
the tech who came to my house did say that " No power to main harness of ML amp from battery . 25A service.
that is the wire run i am really trying to find and i fell like if i can find that wire run and all the conectors between the 25amp sourse from battery to Main Harness i will beable to find problem
going to run self diagnostic now , unless you need the nav screen, because that has no power either.
Main wire. You should also be reseating all connectors on the driver and passenger side junction blocks. The connectors are on the side of the blocks. BE CAREFUL WITH YELLOW CONNECTOR. They are part of the airbag system.
thanks so much for the help. i will re check and reseat all of those. When you say becareful of the yellow ones they are for the airbags. shol di reseat those too just with lots of care or just leave the yellow air bag ones alone.
THANKS SO MUCH
I feel like im geting closer to a functioning radio and NAv.
Is this the same reason why my nav screen wont go on at all, even though i have power to nav in trunk just not amplifier.
Do you find mice's drops on your garage floor. If you do, mice might chewed your harness. Back in 1995, I had mice chewed my LS400 harnesses. Lexus dealer found it and replaced with new harness. Hope it isn't your case, but you will never know. Just a thought.
You know this is getting a bit much to do over the forum. For $15 you can get two full days of access to https://techinfo.toyota.com/techInfo..._faq_page#sub5 where you’ll have access to all of data, all the service manual, in a much easier to understand then all these images. Or, if you think two days isn’t enough there is a different fee for 30 days.
thanks so much for the help. i will re check and reseat all of those. When you say becareful of the yellow ones they are for the airbags. shol di reseat those too just with lots of care or just leave the yellow air bag ones alone.
THANKS SO MUCH
I feel like im geting closer to a functioning radio and NAv.
Is this the same reason why my nav screen wont go on at all, even though i have power to nav in trunk just not amplifier.
04-29-18, 12:19 PM
2004 sc430 no power from radio to amplifier
