ivers

Hi.

I'm aware of this problem might have been posted here 31337 times earlier, but I can't find any of this with search or browsing the forums, so I ask.

I got this Becker BE-1650 Headunit that I replaced with a Boss HU.
I got a Scosche SLC4 signal limiter between the new HU and the BOSE amp
in the rear. But here starts all the funny problems.

I start my car. Power up the HU. Music and everything works like a charm.
But the speedo gets a half-dimmed backlight (isnt supposed to be there before I
hit the light switch) and my close up lights go off (park lights are still on, my xenon close range lamps go off (norwegian car, it's required to use lights in the day)). Well well, what a cool function. I turn on my stereo, my headlamps turn their self off.

But the problems don't end there.

When I hit the light switch everything turns it self on. Lights in the dash, speedo, headlamps etc. And the stereo goes fubar. Signal noise from hell.
Sounds like the engine getting reborn through the stereo. Dynamo interference.
But the interference only plays in the rear speakers, none of the front.
(When I don't flip the light switch it plays in all the speakers)

I've used almost a day now googling and searching forums for a solution, and didn't even come up with a wiring chart for the ISO contacts orginally installed in my Mercedes.

Further info, it's a 1997 E420 S210.

Anyone familiar with this ?

(And excuse me for my excellent english writing skills )

Diesel Benz

I'm not familiar with these head units but in order to get help from others, could you give your car build date more accurately. There is a change from 02/97 to 03/97.

I understand your car having Sound system. From which car/model/year is the new head unit from? There are further changes from at 1999. I also assume your new head unit has an internal amp, this is why you are using level shifters?

If your speedo gets some back lights when they should not, you must have incorrect power and/or illumination feed.

Why not test the new amp without connecting it to the bose amp, try some temporary loose speakers. Connect only live power and ground, I assume your car does not use CAN bus to the head unit, is that right (should be there from 1999 onwards)? Don't connect the illumination wire and speed signal etc. And double check the power and ground (I assume you actually have both the switched and permanent live wire, the permanent was removed 1999).

PS. even if my skills do not qualify judging your writing, I do feel you own an apology, you put many with English as their mother tongue in shame

ivers

Plant 50
Model E420T
Engine 119985 12 013621
Transmission 722625 00 130229
Tyres
Primary CONTINENTAL
Order 0 6 240 02003
Lights HELLA
Cab 00000
Delivery date 04.11.96
Dealer Ravensburg branch (240)

512 radio Becker Europa cassette
radio MB Special with traffic news decoder (VK), with RDS (с 01.07.1992)
810 loudspeaker, sound package
sound package (bose) (с 01.12.1986)
819 CD changer - alpine - in trunk (с 31.07.1992)

---------------------------------------------------------

The brand of the orginal HU says

"Becker Automotive Systems"

Brand/type: SPECIAL
Model-No: BE 1650
Mercedes Part no: 003 820 55 85 [03]
Production year: 1996

---------------------------------------------------------

As described over the speedo backlight turns on half-dimmed if I hit the light switch, but the player is still on with interference from the dynamo.
What wrong power source I got I can't understand, the orginal becker hu works with it.

There should not be any canbus in my car as I don't have any other equipment as steering wheel control or phone.

Diesel Benz

This clarifies the details for your original equipment in the car. Can you post more details about your new head unit, like the MB part number? Or is an after market, not MB OEM unit?

ivers

It's a aftermarket HU, manufacturer is Boss.

4x50w amp, cd/dvd-r mp3 player, usb/memory card connection.
But that isnt what you want to know I guess.
It has a standard ISO DIN connection thou.

Diesel Benz

Sounds odd, I tried to check the Boss unit's pin assignment but if it is following the DIN standard, that should match pretty well with your car.

Your car connector should follow the pin-out of the attached Audio 10 figure, the Becker Mexico assignment. The wire colours are not all the same!

If you have the pin assignment for your radio, check those against this figure.

The behaviour of your car is really odd. I could think of something odd if you had an incorrect illumination feed, but not what your describing. Another option would be a very high current draw that would make one of the car control units confused, I would expect a blown fuse in this case.

I would repeat the suggestion to try the head-unit alone with some temporary speakers or just without speakers, once you've checked that the wiring on your car matches that the new head unit expects.

ivers

Hi again!

The HU works like it should when I hook up the orginal Boss ISO plug that followed the player. (It only has 4 cables to the DIN Plug, GND, Permanent 12v, ACC and Antenna Power) but I don't have any temp speakers.
I will get on to this later this day, now that I have a wiring chart you
turn out to be helpful as I now know what the different cables is.

Thanks, I'll try it after work.

ivers

Thanks Diesel Benz.

That made me understand more of the build.

Thou I found out that the BOSE amp has remote on from the ignition, not from the HU (strange ey ?)

Working like a charm

Anyways.. thanks again.