My cassette player stopped working, and it's what I run my navigator and
mp3 through. I've asked, and it's sort of not worth it to repair.

How hard is it to install another radio, like a Sony, or Pioneer, etc., and how much will it destroy my life? I don't want to install it, then find out my headlights don't work, you know.

Thanks,

Jeff 1991 300d

This depends in part on whether the "cassette player" you say stopped working is the original factory radio or whether it's aftermarket. If it's aftermarket, how badly boogered is the wiring from whoever installed it?

Once you have sorted out the wiring, installing any DIN-size radio/CD player/whatever should not be hard. Try to get a chart of wire color codes for your car so that you can attach the new radio correctly.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

If your replacing the factory original, then there should be a color code chart or table of wiring on the back somewhere showing you where everything goes.

It's not hard, but it is a little time consuming. If your not sure of your skills, then have it professionally installed!

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http://www.mobile-phone-solutions.com Advice on cell phone signal antennas and amplifiers.

So you can have your wires professionally cut up?

The wiring on these radios is so simple. Power, illumination, switched power, and ground are on one plug. Each speaker out (there are only two, the wheel in the console does the fade control) has it's own labeled plug, there is a spade connector for the automatic antenna, and the antenna input. If you can help it don't cut up the OEM harness. You'll be happier later on down the road.

EDIT: I just read you have a 1991. That makes life MUCH more difficult as you don't have any speaker wires at the back of the radio, or any antenna wires. The head unit just controls a tuner computer in the trunk, which runs amps (which I believe are mounted in the trunk of your model as well). I would do some more research before you continue. The previous owner of my '91 SDL took the car to have an aftermarket radio installed, and that resulted in 14 cut wires. I just now got it all put back to stock.

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

If it's the factory Head Unit, go to Crutchfield.com and order a new stereo, a wiring harness adapter and faceplate adapter. They will even send you an instruction sheet with detailed removal and replacement instructions.

If it's already been replaced, you might have a messy nest of wires back there.

__________________
Chad
2006 Nissan Pathfinder LE
1998 Acura 3.0 CL
OBK#44
"Pleasure in the job puts perfection in the work." - Aristotle (384-322 B.C.)

SOLD
1985 300TD - Red Dragon
1986 300SDL - Coda
1991 - 300TE
1995 - E320
1985 300CD - Gladys

Here is a wiring diagram for your system, minus the amps for the speakers.



-J

cutting up the wiring is not professional! Get the adapter plug that will let you install your stereo into the factory plug.

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http://www.mobile-phone-solutions.com Advice on cell phone signal antennas and amplifiers.

With a 1991 there is no adapter harness per-say, you have to run speaker wires form the head unit to where the amps are, and an antenna wire to the head. I don't know if adapter plugs for the amps are available.

-J

The problem is the amp in the trunk. You'll need to, at least, run a long antenna wire extender. They make an adapter to tap into the amp but unless you buy a very low power head the amp will be way overpowered on the front. I sprung for this for my 91 350SD...

http://www.valordvd.com/product/productinformation.asp?pc=Navigation&productid=NVG-720W

So I didn't have to drag a separate GPS, hands free headset, etc. That unit is single DIN and looks fine installed. I actually changed out the speakers at the same time for Infinitys. The "Don't cut the wires" thing has some merits, I compromised by using the adapter just for the power/power antenna connections, used a 10' extension for the antenna, and ran new wires for the 4 speakers I used, bypassing the amp completely. I didn't use the speakers in the doors, replaced the rear 3 ways with 5.25" round and the Dash with 4.25" ovals. Stashed the NAV computer and the XM reciever in the passenger footwell, GPS antenna on the dash, and XM antenna run up the rain channel and roof mounted. Backup camera is mounted to the license plate frame, so at this point I haven't done much I would consider abusive to the old girl (no holes drilled) and frankly consider the deck a huge improvement to the car. In-dash GPS just like a new car might have!!

Bypassing the amp means the bizarro console fader doo-hickeynow does nothing but sit there. It was a dumb place for a fader anyhoo.

I saved the stock deck and speakers, stashed in my garage against the day that 1991 SDs are so collectible that having those original parts will be important.

It was a BIG project, but the BBB is my mobile office and we do 1000 miles plus a week. Probably the best thing I could have done for the car.

__________________
Lynrd

The BBB - 1991 350SD, 166,000 miles
1993 HD FXRS-CONV
1988 BMW R100RS

Whn installing a new head unit I'd recommend running fresh wire and soldering to the speakers/HU plug.

My new 56W RMS headunit and some 4.5" and 5" speakers along with soldered 14gauge wiring is louder than I can stand: Even with all the windows down at 70mph I can only bring myself to bring the radio up to 40/60 (and even that's uncomfortably loud)

If I could go back I would have just installed the front 4.5" speakers and then thrown a "basszooka" or similiar into the backseat and skipped the rear speakers.

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