Everything on the screen on the entertainment system works but I get no sound. All the buttons work. I can change stations, adjust volume, switch between different functions, etc., etc. but all without sound.

The cassette player runs but without sound. The CD player shows the CDs but does not run (when running the screen displays a tracking number also when I check the unit in the boot [trunk to Americans] nothing is happening).

I checked all fuses and reset the ECUs (battery disconnect, etc..) but that didn't work. It was suggested that the CD player needed replacing. I have done that to no affect. The two CD players act in exactly the same way. It has now been suggested it may be the amplifier. I do not want to spend any more money on fixes that don't work.

There was no previous indication of a potential failure. I normally leave the radio on and when I started the car the radio came on but without any volume.

 

Do you have the premium system (can be identified by amplifer over top of the CD changer, behind the carpeted panel) ?

 

Yes, it is the Premium system with the amplifier.

 

Just want to confirm that you checked fuse #18, 30 Amps in the trunk fuse box for the amplifier.

 

According to my handbook, fuse 18 is unused. Fuse 9 does the amplifier and electric aerial. In the boot (trunk) fuse box there is no fuse in slot 18 and slot 9 has a 10 amp fuse. I should have mentioned earlier that the electric aerial (on the same circuit as the amplifier) still works.

 

OK, I was looking at a year 2000 circuit diagram because I did not have a '99. I went back and looked at a '98, and that matches what you describe.

It looks like the amplifier system changed betwen '99 and 2000. The early one, like you have appear to be a conventional amp, the later ones are more intelligent versions on the AI-Net. That may actually be used to your advantage for easier troubleshooting.

It appears that there are two connectors on the amp, a small one with solid color wires, and a large one with striped wires. The large one with striped wires are the speaker outputs.

The small one with solid wires appears to contain the signal inputs. The solid green is signal ground. The solid red, blue and yellow wire appear to be signal inputs. If you have an audio amp with speakers with line level inputs you can use as a tester, you can see if you can hear a signal between the green (signal ground) and the red or blue or yellow (signal) wires. If you do, your headunit is working and your amp is probably bad. If you do not, you may have a headunit problem.

 

Thanks. I have a BOSE unit which I may be able to rig up to test the head unit. Since everything otherwise seems to work perfectly in the head unit, I am inclined to believe it is the amplifier.

 

I posted a request for information on my non-working entertainment system. The result was that I needed a new amplifier. The amplifier arrived yesterday but is the wrong one. I requested a LJB4170BA but received a LNF4170AA, Can I substitute the LNF4170AA for the LJB4170BA?

 

I don't have the answer . But the parts catalog definitely shows them as distinct and for separate years.

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