No Sound: '04 ML w/Nav (1 Viewer)

[cek347]

Just picked up an '04 GX with ML and Nav. PO said the radio sometimes comes on....and most times doesn't. He said just leave it on and sometimes it will turn on by itself. There is no crackling or popping. Just comes on and works and sounds great and all speakers are working. Most of the time though nothing. When you turn the radio on it shows on on the Nav and when you turn off it says its off on the nav. When you turn it on and attempt to adjust any audio settings you cant move or adjust anything in the Audio screen on the nav.

Some searching points to ML amp troubles and replacement and magical fuse replacement cures. I found the Lexus TSB on stereo system trouble shooting. That was in a thread over here

I put the NAV unit in diagnostic mode and I get this:

and this:

For the NCON (no connection) the TSB says to check for continuity of TX+ and TX- from head unit to amplifier. Not sure how to do that. I found a wiring diagram from searching. I'm guessing I need to pull the head unit out or can I check the continuity on the Amp plugs?

Any advice for work I could do on my own would be helpful. Thanks.

 

[Don65GX]

Any update? Mine is doing the same thing.

 

[bcomnes]

Lol mine just started doing this. Comes back on its own eventually. Anyone figure this out?

 

[greenscobie86]

Had the same issue. Sometimes sound would work for a couple of minutes, and sometimes would not work at all. Sent off the Amplifier to be rebuilt by United Radio in NY and no more problems. VERY common failure on ML amplifiers apparently.

 

[bcomnes]

That’s the extent of what I can find out. Did they tell you what failed on the amp?

 

[greenscobie86]

That’s the extent of what I can find out. Did they tell you what failed on the amp?

I've done a fair bit of research on why/how the amplifier fails but was not able to make any headway. Some said it was a signal processor that eventually gives up the ghost, others eluded to a poor cooling design(one small fan for the entire amp) causing caps to fail. I cracked open the unit to see if there was anything obvious that I could find to no avail. From what I understand the ML amplifier is essentially a proprietary unit without user serviceable components, so regular DIYers are out of luck... United Radio seems to be the place to go since they are an authorized/official Mark Levinson repair center. I chose to throw money at the problem and sent it off to them. Repair time was only a day or so and they had it shipped back to me pronto, not much info from them as to "what" exactly failed aside from it being a super common problem and they deal with the repair all the time.

 

[bcomnes]

I've done a fair bit of research on why/how the amplifier fails but was not able to make any headway. Some said it was a signal processor that eventually gives up the ghost, others eluded to a poor cooling design(one small fan for the entire amp) causing caps to fail. I cracked open the unit to see if there was anything obvious that I could find to no avail. From what I understand the ML amplifier is essentially a proprietary unit without user serviceable components, so regular DIYers are out of luck... United Radio seems to be the place to go since they are an authorized/official Mark Levinson repair center. I chose to throw money at the problem and sent it off to them. Repair time was only a day or so and they had it shipped back to me pronto, not much info from them as to "what" exactly failed aside from it being a super common problem and they deal with the repair all the time.

Sorry one last round of questions: Did you have to wait for your amp to be reliably dead/failing before you sent it in?

Mine still works most of the time, with bouts of unreliability where you can't get any sound and the amp throws the no-connection error in diagnostics. Funny enough its been working great after I opened it up to look inside (so far).

Also how much did United radio charge you? Home | United Radio this is the site right?

 

[greenscobie86]

The support person explained to me that they will bench test the amplifier rigorously to identify all failed components and repair/replace as necessary. As mine was also very "spotty" in its operation I had the exact same question you did actually.
They warranty the repair for 1 year.

The repair wasn't cheap, around $400+tax+shipping from me to them(return shipping is included in the repair cost.)

That is the correct website, I recommend calling them as they seem to be a little old school in the way the operate. You'll have to print out a PDF form and fill in your details when you send the amp, then they will call you on the phone to request a credit card payment once they finish repair and are ready to ship it back to you.

 

[bcomnes]

Glad I figured this was happening before I installed the GROM unit. I would be pulling my hair out thinking I screwed something up.

 

[bcomnes]

Estimate is $475 (including shipping back). Probably get this done for hopefully another 16 years or so of operation.

 

[DalX470]

Just a FYI/PSA for anyone seeking amplifier repair work in the Dallas/Ft. Worth - just got mine overhauled for my 06 LX (channel controlling the sub was out, among other issues, water damage, etc). Work done by Atlas Electronics. Took a while, but worth it for those brave souls motivated to keep the original ML system throughout.

Home | Dallas, TX | Atlas Electronics, Inc. TV & Projector Repair

Atlas Electronics, Inc. TV & Projector Repair in Dallas, Texas, offer the very best in TV and projector repairs and parts supply.

www.atlaselectronicsinc.com