98 E320 - Replaced Head Unit, No Sound Output
07-27-2010, 09:52 PM
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1998 Mercedes E320
98 E320 - Replaced Head Unit, No Sound Output
Hello mbworld,
First, I'm a new member so please take it easy on me. Great website by the way.
Here's the problem I'm having. I have recently bought a 1998 Mercedes E320 but I soon found out that it has an audio problem: no matter how much you would turn the knob, the volume would quickly max out and it would be at a very low level (you could barely hear it). Initially I thought it may be a problem with the knob itself since it looked worn out and I wanted to go ahead and replace it. However, since the head unit and the trunk-mounted CD changer are a little outdated, I decided to replace the head unit altogether but keep the stock Bose amplifier and speakers. So I started doing some research on how difficult that might be and it turns out it is quite easy. Additionally, since I already had a head unit (Dual XD6150) that was never used sitting around in my house, I decided to go ahead and install it with the intention to buy a nicer HU in the future. After following very useful instructions written by members like MarcusF, I bought a PAC SOEM 4 as well as a Scosche VW01B wiring harness adapter and I went ahead and installed it. Here's where the problem comes in. I am now not getting any sound output at all. The unit is powered, but whether I try listening to the radio or a CD, there's no sound at any volume level, not even a hiss.
I am pretty sure that all the wiring was done correctly. The head unit is connected to the PAC SOEM 4's input, the output is connected to the wiring harness which is in turn connected to the Bose amplifier. I know one thing I do not have yet is an amplified antenna adapter, but I don't think that would be the problem. Could it be that the amp is dead, would that explain the low volume as well? Since the amp is a little pricey to replace, how would I know for sure it's the amp and not something else? Does anyone else have any other suggestions? Any help would be appreciated.
Thanks,
Nick
First, I'm a new member so please take it easy on me. Great website by the way.
Here's the problem I'm having. I have recently bought a 1998 Mercedes E320 but I soon found out that it has an audio problem: no matter how much you would turn the knob, the volume would quickly max out and it would be at a very low level (you could barely hear it). Initially I thought it may be a problem with the knob itself since it looked worn out and I wanted to go ahead and replace it. However, since the head unit and the trunk-mounted CD changer are a little outdated, I decided to replace the head unit altogether but keep the stock Bose amplifier and speakers. So I started doing some research on how difficult that might be and it turns out it is quite easy. Additionally, since I already had a head unit (Dual XD6150) that was never used sitting around in my house, I decided to go ahead and install it with the intention to buy a nicer HU in the future. After following very useful instructions written by members like MarcusF, I bought a PAC SOEM 4 as well as a Scosche VW01B wiring harness adapter and I went ahead and installed it. Here's where the problem comes in. I am now not getting any sound output at all. The unit is powered, but whether I try listening to the radio or a CD, there's no sound at any volume level, not even a hiss.
I am pretty sure that all the wiring was done correctly. The head unit is connected to the PAC SOEM 4's input, the output is connected to the wiring harness which is in turn connected to the Bose amplifier. I know one thing I do not have yet is an amplified antenna adapter, but I don't think that would be the problem. Could it be that the amp is dead, would that explain the low volume as well? Since the amp is a little pricey to replace, how would I know for sure it's the amp and not something else? Does anyone else have any other suggestions? Any help would be appreciated.
Thanks,
Nick
07-27-2010, 10:03 PM
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GL450
Did the car come with the stock headunit, or aftermarket?
My guess is that the amp isn't getting the turn on signal from the headunit you wired in. Did you connect the blue wire on the headunit to the blue wire on the wiring harness?
Other option, on your head unit since you used RCA connections with the PAC, do you need to go into the radio setup menu and choose RCA output? Many radios have the preouts turned off and you have to turn them on.
My guess is that the amp isn't getting the turn on signal from the headunit you wired in. Did you connect the blue wire on the headunit to the blue wire on the wiring harness?
Other option, on your head unit since you used RCA connections with the PAC, do you need to go into the radio setup menu and choose RCA output? Many radios have the preouts turned off and you have to turn them on.
07-27-2010, 11:21 PM
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2001 E320 - RIP
hey Nick....x2 on Saintz tips....the dual's preout is 2v....if using the hu rca out to the SOEM, the SOEM requires 4v on the RCA input (see note on install sheet)....try using the individual speaker wires from the hu to the SOEM and see if that works for you....good luck!
07-28-2010, 08:55 AM
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GL450
With a 2V preout you should be able to hear it, but it will be really quiet. If you've got no sound something is wrong. But yeah, you'll need to either rewire to use speaker outs, get a 4v+ radio, or listen to really quiet music.
......"you'll need to listen to really quite music"......right on!
07-29-2010, 10:07 PM
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1998 Mercedes E320
Sorry for the slow reply.
Yeah, the car came with the stock head unit, but it had the volume problems I mentioned. As for the blue wire, I am not sure. There's a blue wire that comes out of the Dual head unit that is not connected to anything. There's another blue wire that comes out of the PAC SOEM 4 that is also not connected to anything. Are those supposed to go anywhere?
Regarding the connections, I didn't use the RCA connections, I just used the wires. In other words, the head unit is connected via the wires to the PAC SOEM's Input. All wires are connected except for that blue wire I mentioned. The PAC SOEM Output is then connected to the wiring harness adapter and the adapter is in turn connected to the amplifier.
Having said that, I think you guys are right. It may simply be that the Dual's preamp output of 2v is not enough. But the thing is, I am not hearing anything. Shouldn't I hear at least something at low volume? Maybe 2v is just too little for any sound to be put out?
I am going to look for a 4v preamp output head unit and hopefully that will solve the problem. Thanks again for the help.
Yeah, the car came with the stock head unit, but it had the volume problems I mentioned. As for the blue wire, I am not sure. There's a blue wire that comes out of the Dual head unit that is not connected to anything. There's another blue wire that comes out of the PAC SOEM 4 that is also not connected to anything. Are those supposed to go anywhere?
Regarding the connections, I didn't use the RCA connections, I just used the wires. In other words, the head unit is connected via the wires to the PAC SOEM's Input. All wires are connected except for that blue wire I mentioned. The PAC SOEM Output is then connected to the wiring harness adapter and the adapter is in turn connected to the amplifier.
Having said that, I think you guys are right. It may simply be that the Dual's preamp output of 2v is not enough. But the thing is, I am not hearing anything. Shouldn't I hear at least something at low volume? Maybe 2v is just too little for any sound to be put out?
I am going to look for a 4v preamp output head unit and hopefully that will solve the problem. Thanks again for the help.
07-29-2010, 11:20 PM
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2001 E320 - RIP
hey man....your wiring sounds good....connected straight up, the SOEM will drive it to 4v (up to 12v per specs) .....go ahead and connect the blue wires on the radio side....is there a blue wire on your mb harness, what's on pin 5?....that is the remote on for the amp (used to be power antenna)....connect the SOEM 'remote amp on' to the wire in pin 5....
Last edited by kbad; 07-29-2010 at 11:26 PM.
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07-30-2010, 09:44 AM
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GL450
If you didn't use the RCA connections, you're not using the pre-outs, so the 2V shouldn't be the issue. You just need to connect the blue wires. What's happening now is the head unit isn't turning the amp on. Once you connect that blue wire, it will turn the amp on and you'll be set.
07-30-2010, 07:16 PM
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1998 Mercedes E320
Oh, OK.
Well, there's technically 4 blue wires. There's one that comes out of the Dual head unit (page 3 here: http://www.dualav.com/support/manuals/xd6150.pdf) that apparently should be connected to the amplifier. There's another blue wire that is connected to the Input side of the SOEM (http://www.pac-audio.com/PACProductD...ons_100209.pdf) which is the Remote Amplifier Trigger. One other blue wire comes out of the SOEM and the diagram states that it should be connected to the amplifier. Finally, there's a blue wire on the Mercedes harness (pin #5).
I assume that all of them need to be connected, but in which order? Is the blue wire from the head unit supposed to be connected to the Input blue wire on the SOEM and the Output wire connects to the MB harness #5?
Well, there's technically 4 blue wires. There's one that comes out of the Dual head unit (page 3 here: http://www.dualav.com/support/manuals/xd6150.pdf) that apparently should be connected to the amplifier. There's another blue wire that is connected to the Input side of the SOEM (http://www.pac-audio.com/PACProductD...ons_100209.pdf) which is the Remote Amplifier Trigger. One other blue wire comes out of the SOEM and the diagram states that it should be connected to the amplifier. Finally, there's a blue wire on the Mercedes harness (pin #5).
I assume that all of them need to be connected, but in which order? Is the blue wire from the head unit supposed to be connected to the Input blue wire on the SOEM and the Output wire connects to the MB harness #5?
Last edited by ncodita; 07-30-2010 at 07:20 PM.
08-01-2010, 08:03 PM
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1998 Mercedes E320
Yeah, it turns out that everything was good except the blue wire needed to be connected...All I did was connect the blue wire that came out of the PAC SOEM to pin #5 and now everything works perfectly. 
You guys are amazing, I really appreciate the help.
Thanks again,
Nick
You guys are amazing, I really appreciate the help.
Thanks again,
Nick
11-22-2014, 01:04 PM
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1996 mercedes S500
Question: Using both the bose amp and a sub amp.
Looks like I'm bringing up an old thread. I'm in the process of installing an aftermarket Head unit in to my 01' E320 with the factory bose system. I currently have an aftermarket sub and amp wired up and installed in the trunk. It sounds like I need to use the blue remote wire to power on the Bose amp, so how do I go about powering the second amp. Am I able to splice in to the blue remote wire from the HU and have that wire feed to both amps, or is there a separate wire I need to use for each amp? Thanks
01-19-2015, 10:22 AM
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1999 e320
didn't need the PAC some
Hello mbworld,
First, I'm a new member so please take it easy on me. Great website by the way.
Here's the problem I'm having. I have recently bought a 1998 Mercedes E320 but I soon found out that it has an audio problem: no matter how much you would turn the knob, the volume would quickly max out and it would be at a very low level (you could barely hear it). Initially I thought it may be a problem with the knob itself since it looked worn out and I wanted to go ahead and replace it. However, since the head unit and the trunk-mounted CD changer are a little outdated, I decided to replace the head unit altogether but keep the stock Bose amplifier and speakers. So I started doing some research on how difficult that might be and it turns out it is quite easy. Additionally, since I already had a head unit (Dual XD6150) that was never used sitting around in my house, I decided to go ahead and install it with the intention to buy a nicer HU in the future. After following very useful instructions written by members like MarcusF, I bought a PAC SOEM 4 as well as a Scosche VW01B wiring harness adapter and I went ahead and installed it. Here's where the problem comes in. I am now not getting any sound output at all. The unit is powered, but whether I try listening to the radio or a CD, there's no sound at any volume level, not even a hiss.
I am pretty sure that all the wiring was done correctly. The head unit is connected to the PAC SOEM 4's input, the output is connected to the wiring harness which is in turn connected to the Bose amplifier. I know one thing I do not have yet is an amplified antenna adapter, but I don't think that would be the problem. Could it be that the amp is dead, would that explain the low volume as well? Since the amp is a little pricey to replace, how would I know for sure it's the amp and not something else? Does anyone else have any other suggestions? Any help would be appreciated.
Thanks,
Nick
First, I'm a new member so please take it easy on me. Great website by the way.
Here's the problem I'm having. I have recently bought a 1998 Mercedes E320 but I soon found out that it has an audio problem: no matter how much you would turn the knob, the volume would quickly max out and it would be at a very low level (you could barely hear it). Initially I thought it may be a problem with the knob itself since it looked worn out and I wanted to go ahead and replace it. However, since the head unit and the trunk-mounted CD changer are a little outdated, I decided to replace the head unit altogether but keep the stock Bose amplifier and speakers. So I started doing some research on how difficult that might be and it turns out it is quite easy. Additionally, since I already had a head unit (Dual XD6150) that was never used sitting around in my house, I decided to go ahead and install it with the intention to buy a nicer HU in the future. After following very useful instructions written by members like MarcusF, I bought a PAC SOEM 4 as well as a Scosche VW01B wiring harness adapter and I went ahead and installed it. Here's where the problem comes in. I am now not getting any sound output at all. The unit is powered, but whether I try listening to the radio or a CD, there's no sound at any volume level, not even a hiss.
I am pretty sure that all the wiring was done correctly. The head unit is connected to the PAC SOEM 4's input, the output is connected to the wiring harness which is in turn connected to the Bose amplifier. I know one thing I do not have yet is an amplified antenna adapter, but I don't think that would be the problem. Could it be that the amp is dead, would that explain the low volume as well? Since the amp is a little pricey to replace, how would I know for sure it's the amp and not something else? Does anyone else have any other suggestions? Any help would be appreciated.
Thanks,
Nick
01-19-2015, 10:34 AM
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1999 e320
this is what I did to mine
Looks like I'm bringing up an old thread. I'm in the process of installing an aftermarket Head unit in to my 01' E320 with the factory bose system. I currently have an aftermarket sub and amp wired up and installed in the trunk. It sounds like I need to use the blue remote wire to power on the Bose amp, so how do I go about powering the second amp. Am I able to splice in to the blue remote wire from the HU and have that wire feed to both amps, or is there a separate wire I need to use for each amp? Thanks
02-26-2016, 11:19 AM
#17
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I have a 1998 E300TD and will be installing a new Alpine Bluetooth unit with my stock system. The car has the CD changer in the trunk and 'Bose' name plates on the rear shelf woofers with the Bose amp in the RR trunk-fender well (under the liner).
I have the Crutchfield harnesses, one for the Bose system and one without, just in case.
I will know more once I pull the old radio from the car, to see what wires I have available to me. The new harness adapter for the Bose system has the RCA plugs.
I have the Crutchfield harnesses, one for the Bose system and one without, just in case.
I will know more once I pull the old radio from the car, to see what wires I have available to me. The new harness adapter for the Bose system has the RCA plugs.
