audio volume turns off after a few mins
 

hi guys, i have a 2003 l322 range rover ( x5 in disguise ) the prob i have is after a few minutes the audio turns off. if i push the button and turn off then back on ,it comes back on for another few minutes, then back off again. this just continues , on ,off,on ,off always for the exact amount of time? can anyone point me in the right direction? thanks in advance :)

thought id better say , it has mk3 nav, m54 radio, tv tuner and dsp and the fault is accompanied with any others

Is this what you are experiencing? Is your nav screen dead? Did you replace the DSP amp?
Troubleshooting blank nav screen and radio shut off

interesting link but no my nav works fine and the dsp is original, but the link suggests the nav maybe the problem, if noone can come up with an answer i may remove the nav unit and see if it still happens. i believe audio still works when you remove the nav unit?

The problem is that the DSP amp is not communicating with other components it needs to see on the car's I-Bus. If your nav is working normally and the radio functions are normal (other than the shut-off) then you have a mystery. Does the volume control work, either on the dash or steering wheel?

The other potential cause is a failing battery. How old is your battery? I have seen this symptom first-hand when my battery neared its end of life.

radio and cd work fine volume works on head unit and steering wheel and the battery is is 2 months old , tested is today at 12.75v so bugger!?

am i right in saying i can take out the nav and audio should still work? or will the dsp recognise it as missing and shut down?

Yes, the audio will work with the nav system removed. However it will do what yours is already doing-- shut off after a couple minutes.

I am thinking that your amp needs recoding. Or your amp simply went bad.

do you think its deff the dsp? or could it be the mb54?

Go back to the root cause: The DSP amp will shut itself off if it does not see either the DSP controller (separate controller, nav computer, or MID, depending on the car's configuration) or the radio over the car's I-Bus. This can be for several reasons:

1) Radio module disconnected
2) Nav computer disconnected or faulty
3) I-Bus fault
4) Amp coded for non-nav in a car with nav or TV (or vise versa)
5) Low battery that degrades module performance and causes unrelated symptoms
6) Internal module fault that affects I-bus communications

Since the screen works, your radio station changes, and volume works, etc. you can rule out any major module failures like #1, #2, or #3. Since this is the only symptom you mention on the I-Bus, you can probably also rule out a general I-Bus fault like #4. You say your battery is new, so that potentially rules out #5.

That leaves an internal fault in a component that allows all other functions to work but I-Bus communications related to component presence (#6). This is a very low probability, so I would go back to #4 or #5 as more likely.

you can remove nav, the tv module will take over menu generation... do you have bluetooth? when radio goes dead, does it MUTE or does it TURN OFF? what happens when you choose the TV module? the TV audio is fed through the radio, so if the radio loses power, the TV will go mute - does it?

No, I don't have Bluetooth, and the tv no longer works because the analogue signals have been turned off in the u.k and its not worth the cost of converting to digital. Also I believe the audio is muteing rather than turning off. Any ideas?

Replace the DSP amp. Then get the new amp coded in the car.

ive ordered a used dsp but its out of the sme vehicle , does it still need codeing? or are they just coded to a specific make and model of vehicle?

They are coded to model and radio type (standard vs. non-nav). So, if your replacement amp is from a l322 range rover with TV or nav, it should work plug-and-play. However, if either of those parameters is different, it will need coding.

great thanks for your help, i now understand the system a lot better down to you

well after,taking ou all the modules and cleaning there connections it works sometimes and not others, what ive noticed is sometimes the on off orange light glows bright as it should and other times its hardly noticable and seems to flicker.any idea what could cause this? i think ifs related to my problems

Have you installed the replacement amp yet? Did you get it coded after installation?

Yer new amp fitted , didn't get it coded as its out of same make and model

So the replacement amp had no effect on the radio shut off symptoms?

No, it doesn't do it every time now , but I think that's a coincidence , as I had all theodules out for a week or so , cleaning them up

So, back to this post... http://www.xoutpost.com/915371-post10.html ... the amp does the shut-off thing when it does not see what it expects to see on the car's I-Bus. The problem could still be amp coding. But, the fact that it is intermittent seems to indicate a connectivity problem.

I know for certain that a disconnected nav computer (or MID in non-nav cars) or radio will cause the amp shut-off behavior. I do not know if a disconnected screen will cause the problem; I have never tested that first-hand. Maybe that is the issue.

Do any of the screen buttons or knobs seem unresponsive? You mention the radio on LED, are there any other symptoms you can identify? In general, are there any other symptoms in your car overall that seem odd?

Everything in the car seems to be perfect , the led seems to be the only indication of a problem what could cause it to glow like the sun on minute and be so faint the next? If I can find the reason I think it wiil lead me to the fault