Amplifier

[CLUBCAPT]

Intermittent amplifier. Check and repair. I have had an intermittent sound coming from the Mark Levindon Amplifier in my SC430 so I have got to it and it felt like one of the connectors worked its self loose, only about 1 or 2 mils but since I shoved it back in 5 days ago it has worked flawlessly since. Try before you buy!!!!

Gary

[Dr Philip]

Thanks, Gary your post gives me hope!! My radio has ceased to work or omit any sound to be correct. The radio would appear to be working both on CD's and broadcast but no sound.

I will obviously check al fuses and perhaps check the radio connections first, and then move on to the amplifier.

Hope it's as simple as a plug worked loose!

 

Philip

[Neil E]

Unless someone has been working on/behind the head unit or the amp, it's more likely a fuse than a plug working loose. The connectors have retaining clips so they shouldn't work loose but the connection within the Mark Levinson (Harman) amp can develop a fault. It's a known flaw that appears with age, more so with other models than the SC430. In some cases pushing the connector may produce a temporary fix.

If the head unit turns on but there's no sound, check the fuse for the amp and try adjusting the fader/balance/bass/treble. If the head unit doesn't display the menu, it's a good indicator that the remote connection between the head unit and the amp isn't working. It's also a known cause for batteries going flat overnight as in some cases the amp does not remote switch off when the ignition is turned off. The fault in these cases is with the connection in the Harman amp.

[Dr Philip]

That is really useful information Neil, thank you.

I don't suppose you know offhand which fusebox and the number of the fuse to check?

The head seems to be following the buttons pressed and 'plays' cd's all without sound.

 

Philip

[Neil E]

Hi Philip, did you try the balance/fade/bass/treble menu? If it doesn't display on the head unit then that points to a problem with the amp in the boot or at least the connection to it.

There are 3 radio fuses, try the 30A Radio No1 fuse under the bonnet near the Battery. Lift the cover and the diagram should be inside the cover.  It may be fuse 47 if it's the same as the US models. It also feeds the antenna and sat nav so if they are working then the fuse should be okay.

The 10A and 7.5A radio fuses are in the footwells. If you take the covers off it will confirm the locations on the back of the covers, I doubt the fault is with either of those. 

[Dr Philip]

Hello Neil

Yes, the fade/balance do display on the screen. The other strange thing is the wooden cover has stopped working? Hopefully I will get round to checking the fuse in the next day or two, if able. This all seems to have happened when I had a flat Battery - which may have nothing to do with anything.

If the sun comers out, it will not stop me from enjoying the hood down - assuming that will work!!!!!!!!

Philip

[Neil E]

On 5/11/2023 at 1:39 PM, Dr Philip said:

Hello Neil

Yes, the fade/balance do display on the screen. The other strange thing is the wooden cover has stopped working? Hopefully I will get round to checking the fuse in the next day or two, if able. This all seems to have happened when I had a flat battery - which may have nothing to do with anything.

If the sun comers out, it will not stop me from enjoying the hood down - assuming that will work!!!!!!!!

Philip

Hi Philip

Did the Battery go flat overnight or was it over a week or two? Was it drained completely or just a bit under 12 Volts?

A working fade/balance display suggests the amp may be okay, let's hope so. Best check the footwell fuses too if the audio door isn't closing, that may be a clue. Also, just a thought, do you have a handsfree phone interface that might have muted the audio signal?

Does the volume number go up and down? It's so long since I used the standard system I'm struggling to remember how it functions. 

[kcdionysus]

@Dr Philip Did you get any resolve with your amp problem?

I have a newly acquired SC and there is no sound from the stereo but there is sound from the sat nav system. I did a ‘secret menu’ diagnostic and it can see the amp so I’m hoping it’s something daft. 

[Dr Philip]

No KC - I have not yet sorted the stereo out! Probably just laziness on my part, as we only really use the car when the sun is shining, and then we don't worry about the stereo then.

Let me know how you get on please

[2Tanks]

On 7/9/2023 at 8:35 AM, kcdionysus said:

I have a newly acquired SC and there is no sound from the stereo but there is sound from the sat nav system. I did a ‘secret menu’ diagnostic and it can see the amp so I’m hoping it’s something daft. 

kcdionysus  Can you explain the steps to enter  the "secret menu" please?
I am having the same issue with my head unit totally unresponsive!
Thanks.