Second ML Amp
03-08-16, 07:27 AM
#1
Driver
Thread Starter
Second ML Amp
I'll soon find out if replacing the ML amp for the second time will fix my current problem. All audio except Phone and Nav will cut out after about 15-20 mins of driving or if simply leaving the car running in place. This only occurs if the car has sat parked over night for at least 8 hours. If the car is turned on more frequently but rests for a minimum of 30 mins I will get about 10 mins of uninterrupted playback/audio. The audio simply drops and you don't hear a single thing. When it drops you no longer get any feedback from the volume **** either, ie you wont see the numbers on the screen moving up or down.
Tried replacing the head unit with a good one and the same thing occurred. In stead of buying a used amp I decided just to take it to the dealer to have them diagnose it. They couldn't figure it out the first day and had to call their global headquarters to speak with engineers for assistance in order to determine the issue. They ultimately came back and said it is the amp. They wanted to be sure it wasn't the head unit or something else as they said this was the first time they've seen one come in with these symptoms, especially with the numbers not showing on the screen when it occurred.
Let's hope they are correct. I had sent the amp to UR a few months ago and they could only bench test it. They concluded it was good. I figured let Lexus tell me what's wrong, and if there is still an issue after this second replacement I can at least take it back and tell them to get it fixed.
Sucks, that this amp was refurbished once before....about 43K miles later and now its gone bad again. Cost for a new refurbished unit is about $1300.
For those who have gone more than 40K miles since your first amp replacement chime in. I really hope this short window is rather rare and maybe my amp got a bad refurbishment job to begin with.
Tried replacing the head unit with a good one and the same thing occurred. In stead of buying a used amp I decided just to take it to the dealer to have them diagnose it. They couldn't figure it out the first day and had to call their global headquarters to speak with engineers for assistance in order to determine the issue. They ultimately came back and said it is the amp. They wanted to be sure it wasn't the head unit or something else as they said this was the first time they've seen one come in with these symptoms, especially with the numbers not showing on the screen when it occurred.
Let's hope they are correct. I had sent the amp to UR a few months ago and they could only bench test it. They concluded it was good. I figured let Lexus tell me what's wrong, and if there is still an issue after this second replacement I can at least take it back and tell them to get it fixed.
Sucks, that this amp was refurbished once before....about 43K miles later and now its gone bad again. Cost for a new refurbished unit is about $1300.
For those who have gone more than 40K miles since your first amp replacement chime in. I really hope this short window is rather rare and maybe my amp got a bad refurbishment job to begin with.
03-08-16, 11:03 AM
#2
Interesting. I hope the second amp solve your problem and keep us posted.
03-08-16, 09:51 PM
#5
Driver
Thread Starter
Interesting, I'll keep this posted updated.
For what its worth, the engineer at UR did say that Lexus originally sent these amps to a different company who did the initial refurbishment. This engineer claimed the original company didn't always do the best of work. So it could be just my luck mine didn't get repaired very efficiently or it was simply a victim of this first company. Of course UR claims they are better at the repair.
The amp was originally replaced in 2011 and I have an 07 model.
For what its worth, the engineer at UR did say that Lexus originally sent these amps to a different company who did the initial refurbishment. This engineer claimed the original company didn't always do the best of work. So it could be just my luck mine didn't get repaired very efficiently or it was simply a victim of this first company. Of course UR claims they are better at the repair.
The amp was originally replaced in 2011 and I have an 07 model.
03-14-16, 07:38 PM
#6
Driver
Thread Starter
Well...got a new amp and 20 mins into my drive back from the dealer the audio cut out again.
So the car went straight back. Not extremely upset it was misdiagnosed but more upset they didn't actually test the car after installing the new amp. Especially considering I told them how long it took before the audio would cut out. They should've tested it before returning the car.
This morning they called to tell me they believe they figured out the issue. There is something wrong with the Lexus Link ECU as it is incorrectly sending a signal to the amp to cut the volume out or mute it. They de-pinned a wire from the amp harness and they've had continuous playback for well over 2 hours.
So the band-aid fix is to leave this wire de-pinned and taped up. The real fix is a new ECU (2K) for a system I don't even use (subscription based). They said should I ever use the subscription and an accident occur, I would have to manually turn down the volume in order to speak with the person from Lexus Link.
They will be refunding me the money I spent on the new amp. The only charge is the original diagnostic labor...roughly $200. Not too bad. Great dealership and good service. Happy to have this behind me and my tunes back!
Posting the info here to help anyone else who may end up with this rare issue.
The wire they de-pinned is a solid blue on the harness plug closest to the rear of the trunk on the amp, pin 24. When the audio cut out, they found only 2.5 volts to that pin. When there is 2.5 volts or less to that pin, the system in this case thinks a Mayday call is active, thus turning down the volume.
So the car went straight back. Not extremely upset it was misdiagnosed but more upset they didn't actually test the car after installing the new amp. Especially considering I told them how long it took before the audio would cut out. They should've tested it before returning the car.
This morning they called to tell me they believe they figured out the issue. There is something wrong with the Lexus Link ECU as it is incorrectly sending a signal to the amp to cut the volume out or mute it. They de-pinned a wire from the amp harness and they've had continuous playback for well over 2 hours.
So the band-aid fix is to leave this wire de-pinned and taped up. The real fix is a new ECU (2K) for a system I don't even use (subscription based). They said should I ever use the subscription and an accident occur, I would have to manually turn down the volume in order to speak with the person from Lexus Link.
They will be refunding me the money I spent on the new amp. The only charge is the original diagnostic labor...roughly $200. Not too bad. Great dealership and good service. Happy to have this behind me and my tunes back!
Posting the info here to help anyone else who may end up with this rare issue.
The wire they de-pinned is a solid blue on the harness plug closest to the rear of the trunk on the amp, pin 24. When the audio cut out, they found only 2.5 volts to that pin. When there is 2.5 volts or less to that pin, the system in this case thinks a Mayday call is active, thus turning down the volume.
Thread
Thread Starter
Forum
Replies
Last Post
