shunter v8

Active Member
My 2004 l322 radio has been playing up, when I bought it every time I turned the ignition off when I turned it back on I had to turn the volume up as it had turned its self off, today it didn't come on no matter what i did the tape also had no sound, then it just came on with no prompt from me and a few minutes later turned itself off again so it appears to be a loose connection somewhere has anyone any ideas where the best place to start is thanks.
 
Water ingress into the rear Nearside (UK) corner giving the BM54 Audio Amp a soaking....this is the most common cause.
 
Thanks Saint, is it behind the left hand boot panel beside the sat nav, there are two larger units there and one slimmer one underneath the sat nav unit. Is it the one nearest the rear of the car with fins on it, I have shoe a torch in and its bone dry no sign of dampness at all but I suppose the amp could be duff. It seems to come on when you first switch on then fades out after about a minute and won't come back on.
 
The BM54 is the large silver box, Just cos it looks dry doesn't mean it hasn't got wet at some point and fragged it.

Remove the connections to it and look for any corrosion etc.....

It seems odd it comes on them fizzles out though...Still most likely the BM54 as this is the most common item for audio issues. There is a company that can rebuild these units based in West Byfleet (Cartronics I think it is called) might be worth giving them a phone call and discussing your symptoms with them and see what they say.
 
Thanks for your reply saint, the plot thickens I have just been out to have a look with the ignition switched on the radio worked fine for several minutes as soon as I turned on the engine it fizzled out again. If you switch off and on again straight away it does not work.
 
The battery I was told is 7 months old and its charging at 13.8v, i also put it on a trickle charge every week. After more investigations it turns out it's nothing to do with the engine running it justs goes off after about a 2 minutes it was by chance it cut out when i started the engine. I have two large modules in the compartment at the back a black one with fins that i thought was the amp and a silver one in front but it has two what look like AV type leads coming out it as well as the multi plugs is that the amp.i disconnected all of the module leads and sprayed them with contact cleaner but it's still the same it's like something is overheating and cutting out like a thermal cut out as once it is switched off for a while it comes back on for a couple of minutes then cuts off but it's not fading out now just no sound at all.
 
The battery I was told is 7 months old and its charging at 13.8v, i also put it on a trickle charge every week. After more investigations it turns out it's nothing to do with the engine running it justs goes off after about a 2 minutes it was by chance it cut out when i started the engine. I have two large modules in the compartment at the back a black one with fins that i thought was the amp and a silver one in front but it has two what look like AV type leads coming out it as well as the multi plugs is that the amp.i disconnected all of the module leads and sprayed them with contact cleaner but it's still the same it's like something is overheating and cutting out like a thermal cut out as once it is switched off for a while it comes back on for a couple of minutes then cuts off but it's not fading out now just no sound at all.
13.8 volts is no good, on the L322 it should be around 14.7 volts. Sounds like your alternator is sick.
 
Ok thanks for that, I will check it with a proper volt meter as that reading was from one of these plug in type gadgets and are probably not very accurate.
 
I have just tried it with a "real" voltmeter and it's running at 14.2v is that acceptable or still in the danger zone, there are no warnings or other weird things happening.
 
I have just tried it with a "real" voltmeter and it's running at 14.2v is that acceptable or still in the danger zone, there are no warnings or other weird things happening.
Is that at 2K rpm? 14.2 is OK, given the age of the car that may be what was deemed good at the time, these days 14.7 is the norm.
 
Yes that is at 2k rpm, I tried it this morning and it lasted about 2 minutes, I switched off and left it for 10 minutes, switched back on and it turned off after about 10-15 seconds.
 
I had a merc with a similar issue. On that, the problem only manifested in winter when the heater was hot. If you switched on the ac for 20 mins, it would go OK again so you had music but were too cold to listen to it.
Obviously a different setup but on that one, it was a component overheating in the head unit causing it to shut down.
 
Just an update, I spoke to cartronics and without going into too many details I would not use them but I found another company called carphonics a very helpful guy called Baris who went through my symptoms and as Saint had already suggested thought it probably was the BM54 unit. I sent it off to him and was back three days later working perfectly he also does upgrades to the module if required. So we are up and running again with full sound,thanks for everyone's input.
 

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