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93 SL500, 95 SL320, 96 S320, 98 S500, 2002 E320 4Matic Wagon & A little 91 5.0 FORD Mustang
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Yes tuner comes on and and i can change stations. never gotten an error message. But the temp outside needs to be around 40* f. Much below that and the radio lights come on and antenna goes up but no radio cd or tape function. But no error codes
Pop or no pop is not a valid indication. It just means the signal source died before the amp did. The temperature thing is a indication those capacitors are long gone. One cannot just do the amp as the tuner and head unit need to be updated. Now be careful that many places repair the actual problem, but do not rebuild the entire units, so they last another 10 to 20years, yet the repair may last a year or two.

In your case, you need to hook up any old speaker(even from a 2" or so to those two sockets where the black & white connectors plug in. That will qualify the tuner and head unit. Need to put a cassette to see if the sound gets to the tuner electronics in the trunk.

Similar situation on the friend's car (93 600-SEC) I'm working on. Everything works for a few minutes, then with a loud pop, it quits. Occasional popping after that. Until that happens, all channels work and sound is normal. No error codes, and the head unit display is normal. In his case, the antenna works normally. If I turn the head unit off after it's quit working, the antenna goes down.

In my friends case, the amp was recently rebuilt, to the tune of $1000 for repair and R & R. Not sure who did the work.

I don't want to hijack this thread, but the situation is similar, and I thought what helps one might help the other.

Jon
Jon,

Signal source died first over the amp is the popping. The tuner/head unit has to be qualified like above the speaker to see if it quits after a few minutes.

If you like your friend, what you can do to qualify that "$1000" amp repair. is make a audio harness to mate to those two black & white connectors. I believe the flat edge pin is ground and it should be zero ohms to the other flat edge pin. The round pin is the source. You could even solder it up to a 1/8 male stereo jack, and connect to an iPod as your source.
The blue wire that plugs into the amp is the remote turn on, so you will need the radio ON. You can get a 10ft cable run it to a portable radio or ipod...

I'm writing this in-between classes as I'm in school 13hrs a day...

Best of luck,

Martin
 

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1994 S600 Coupe, 1995 S600 Coupe
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Thanks Martin. That was exactly what I was thinking about doing. Glad to know it will work.

His unit comes on, works fine for several minutes, then bang. I need to see if the cassette still works when the radio quits. I know that part of the player works before things crap out, but don't know about after.

This poor guy has been hosed on other "repairs" also. Today I found that a "new" lower radiator hose that a dealer put on was actually his old hose pushed further into the engine outlet, and reclamped. The end of the hose that had failed was still there, sticking out! See below picture.

Jon
 

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1994 S600 Coupe, 1995 S600 Coupe
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A follow-up. I unplugged the CD changer when I removed it to get the carpet out of the trunk on that side. After I plugged it back in, the system hasn't quit after running it for an hour, unlike before.
Looking at the wiring diagram, the CD changer is in series between the head unit and the trunk receiver. So any fault in any of the three (head unit, changer, receiver) will knock things out. There are numerous cable connections that must all work. In my case, it make have been a bad cable connection.
I also pulled the top off the receiver box, and pulled and reseated the three modules inside. I'm not impressed with the receiver construction, being unsealed, with unsoldered modules inside, in an uncontrolled environment like the trunk. The modules don't even plug into connectors, just plated thru holes on the circuit board. That being said, the inside of the receiver was clean. I checked the capacitors visually, and none were leaking or had bulged tops.
I'll be letting it play more in the coming days, and see if it continues to work.



Jon
 

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1992 400se
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Discussion Starter #25
boy you pretty much took over this thread. two completely different issues.
next time you might want to start your own topic
 

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600 coupe, one of the very first built
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I unplugged the CD changer when I removed it to get the carpet out of the trunk on that side. After I plugged it back in, the system hasn't quit after running it for an hour, unlike before.
Looking at the wiring diagram, the CD changer is in series between the head unit and the trunk receiver. So any fault in any of the three (head unit, changer, receiver) will knock things out. There are numerous cable connections that must all work. In my case, it make have been a bad cable connection
This is true but I am surprised you don't get a error message on the head-unit.
I had a poor contact on one of the pins on the 8-PIN DIN connector for the data bus, and even though the CD changer tested on the bench fine, I had troubles. Connecting the cable from the head unit to the tuner box still produced a loud pop. I knew the BOSE was due for repair and indeed, when it was fixed, the sound was crystal clear.
2623378
 

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boy you pretty much took over this thread. two completely different issues.
next time you might want to start your own topic
Sorry. They are similar, and symptoms were like yours. My experience may help you. Did you ever check all of your connections, grounds, cables, etc? If you have a CD changer, try taking it out of the loop and see if the problem persists.

Jon
 

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93 SL500, 95 SL320, 96 S320, 98 S500, 2002 E320 4Matic Wagon & A little 91 5.0 FORD Mustang
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Easy guys... Try it Mr Smith...what Jon has done... Worth the gamble.. The tuner and head unit caps leak, but it is super minor. One has too desolder the caps to see it...

Martin
 
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