ShellyGX

We have a 2004 Lexus GX470 with the Mark Levinson radio system. In the last week it has started to intermittently stop sound coming from the speakers. Would crackle a bit and make some loud clicking sounds then nothing. Now after a few days no sound. We do get sound from the navigation system, guidance cues, etc...

I went into the diagnosis mode holding Audio and Climate and flashing the parking lights 3 times. Here are the diagnostic screens.













It did change when I hit the recheck button. Changed to error or "Check"

Can someone let me know what the problem is with this?

It has the NAV CD under the passenger seat and we had updated NAV through it a few years ago. Is the amp integrated into that box under the passenger seat?

I want to be careful about changing the amp if that is not the issue.

I checked the 2 fuses for radio under the hood and they were good. Are there any other fuses for that? Seems since it is intermittent a fuse wouldn't be the problem.

chiph9

The ML amp is under the driver's seat. You certainly want to check other things first, as it's $1200 at the dealer (there are repair options - there's a guy on eBay that fixes them for around $400)

Try disconnecting the battery for a minute. Remove the negative terminal, then reconnect it with a minimum of sparks (be swift & certain when reconnecting). You'll have to reprogram the auto-windows, the sunroof auto-open, and your saved radio stations (there's a sticky on how to do all that).

Chip H.

ShellyGX

Ok, good idea to pull the negative battery terminal. Did that. On restart the sound came on for a half second or so then back to no sound.

ShellyGX

I contacted the people on eBay who do the repair on the amps. Asked them to look at the thread here and asked them to tell me their opinion on what might be going on. They said take it to the dealer for diagnosis and get part numbers and go from there. Didn't say if it was the amp or not.

Does anyone one know what goes bad in the amp assuming it is that? Seems a high amount of failures and probably same issue that the repair people open up and fix. Like a diode or something? Anyone know specifics?

chiph9

Sorry, I've never opened one, and haven't done board-level repair since the 1980s in the military.

Chip H.

Vmi88

I have a 2004 GX470 with out navigation. Was experiencing the same issues with intermittent working of the radio and popping or cracking sound when you turned it on and off. It has not worked Continuously for months now so I replaced the stereo but there is still no sound. I ordered replaced the amp and still no sound. I checked the fuses and they are good. Unless I got a bad amp from Ebay and both are bad, I am at a loss! Any other ideas?

mrblister

I had same issue . I hit the steering wheel with my fist right on top of the volume switch’s. Radio came on had no happened since , I believe I may have a bad clock spring . If it cuts out again I may change the clock spring


QUOTE=Vmi88;10967707]I have a 2004 GX470 with out navigation. Was experiencing the same issues with intermittent working of the radio and popping or cracking sound when you turned it on and off. It has not worked Continuously for months now so I replaced the stereo but there is still no sound. I ordered replaced the amp and still no sound. I checked the fuses and they are good. Unless I got a bad amp from Ebay and both are bad, I am at a loss! Any other ideas?[/QUOTE]