Toronto300E

My aftermarket radio died so I just reinstalled the Becker Grand Prix 754 Radio that originally came with my 1987 300E and will use one of those cassette adapters to connect my iPhone. I only connected the power harness that powers the radio and the speakers.

I have 4 dashes showing on the display. I understand that this means the anti-theft feature of the radio was activating, making it inoperable unless reset by a Mercedes dealer using a special tool that is made for this purpose. I also understand 4 dashes can appear if the internal mercury (or lithium?) battery inside the unit has died.

I am not going to be connecting the harnesses that connect the radio to the vehicle's anti-theft system. Does this mean that I need not get the internal battery replaced and can merely go to a dealer and have them use that special tool to reactivate the radio? And if I do so, does this mean that unless I have the internal battery replaced in the radio that if I ever disconnect the car vehicle battery that the radio's anti-theft system will enable again and four dashes will appear again. Or, does that only happen if one connects the radio to the car's anti-theft system regardless of whether the radio has an working internal battery or not?

I know that Becker Radio in the US charges $75 to replace the internal battery but then you still have to go to a dealer to get the radio reactivated using that special tool as it has to be done with the radio in the car and some dealers charge $30 for this. I'd rather avoid paying $75 + shipping + filling out customs papers to Becker if I don't have to as this will cost me about $150 from Canada. I am not sure if I'll get a straight answer from Becker as I understand they try to also upsell you on putting in an iPod/iPhone connector in the unit too even (and I am just going to use one of those cassette to speaker jack thingme's).

watut

Call the dealer with your VIN # and they will give you the code which you input into the radio

Toronto300E

Incorrect. As I mentioned, the Becker Grand Prix 754 model radio (which came factory installed in 1986 and 1987 300E's along with some 1988 300E's) does not use the numeric code method to unlock the radio. Only later model Becker radios installed in some 1988 Mercedes and later use this method. My radio requires a special tool to unlock it that only dealers have.

Hence the questions I posed above (which I was unable to find the answers to after researching extensively on the net). I hate to possibly have to pay the $30 dealer unlock fee (sometimes they do it for free I hear) only to find out I still have to send the radio to Becker to get the internal battery replaced and then pay another $150 to do that. I also don't want to pay Becker $150 first only to find out I didn't have to do it and then have to pay another $30. I might as well by a new radio in that case. But for $30 only it's worth keeping this radio which also matches the vintage of the car in terms of stylng.

So, I am hoping someone knows the answers to my specific questions.

Toronto300E

Ok well no one answered my question, but I did call Mercedes in Toronto. They told me that it would be about .3 of an hour or $65 to reset the radio because it requires taking off the faceplate, putting it on, etc. (they obviously do nothing au gratis). Anyway, they also said that there is no way of determining if the internal battery inside the radio is dead (but it likely is since the radio has not been used for 20 years) and if it is it would have to be replaced even if the radio was not connected to the car alarm system after being reset.

The net result of all this is the total cost to reset the radio and replace the battery would be over $200 for me so I might as well by an aftermarket radio (too bad as I already spent $45 buying the custom connectors for the speaker and power wires to replace the ones that were cut off and thrown away by Kromer Radio here when they removed the radio and replaced it with an aftermarket radio 20 years ago)

Saijin_Naib

You try gutting it to replace the battery yourself? I periodically take my BE 4602 apart to snug up some things when the CD drive gets slippy.

Toronto300E

Everything I've read on the forums says you have to send this radio back to Becker in the US to have the battery replaced, so I suspect the battery is not user replaceable. Also a special tool is required to activate the radio after it has been removed from the car, so that further indicates that you likely can't open the radio chassis yourself to get at the battery, but I do see some screws on it. Furthermore, I just called Becker Radio in the US and they say they are not authorized to sell the battery separately. If I want to see what type of battery it is then I'd have to attempt to open the unit to find out, which could destroy the radio as it might not be user-serviceable.

I would think that is it was user-replaceable with a third-party battery that someone on one of these Mercedes forums would have mentioned it.

Does anyone know (for sure)?

BENZITCH

Used in the 1986 and 1987 Mercedes.


Single-piece unit electronic AM, AM Stereo, and FM radio with automatic seek tuning and cassette player (with CrO2 tape switch and Dolby B Noise Reduction), and with anti-theft. Cassette must be manually inserted and ejected.


One of the best AM Sections of any radio ever produced. Had over twice the audio power than the 81-85 version Model 612 which only had 7 watts per channel.


Uses a back-up battery. The radio (used in '86, '87 and some '88 124/126s) was supposed to have a mercury battery that would maintain memory as long as the alarm wasn't set, but the batteries they used went dead within 6 months or a year (rather than the 5+ years predicted).


You can send the radio back to Becker and they will replace the battery for a about $75.


This unit does not have a numerical code. It has a theft deterrent system hooked into the car alarm system.


Came with anti theft circuitry that needed to be reprogrammed at a MB Dealer or Becker when triggered. The model 754 radio was not designed to deactivate when the battery was disconnected. If the 754 is doing that, it simply means that the radio's internal lithium (or mercury?) battery is dead and it needs to be replaced. Once replaced, you can disconnect the vehicle battery and it will not 'dash-out' on you.


If you have 4 dashes across the display the unit needs to be sent to Becker for repair.


If the backup battery is dead, disconnecting the car battery will blank the display and it must be reactivated using the dealer tool with the radio installed in the car. Some dealers (American Service Center in Arlington, VA) will reactivate the radio gratis, some dealers will do it if you slip the service writer a $5-10 bill. Some dealers charge $30 or so to reactivate the radio.


Can be modified by Becker with an auxiliary input to accept an MP3 or iPod.


See Operation Guide.
Becker Grand Prix Model BE 754

Toronto300E

I found all that information too before I started this thread.

So, can anyone answer the questions I posted in my first post? The replies so far repeat readily available information on the internet but nothing dealing with the answers to my questions.

gretta's keeper

I understand your desire to use an original radio, but you are clinging to a penny-wise / pound-foolish ideal. You can get a radio cheaper in Toronto that will get the job done. If you desire using a correct Becker either look for a used working unit with good internal battery (but w/o alarm circuit you'll dash out again) or spend the extra money on what you have - which I'm sorry, but functionally you currently have a "stolen" radio that needs to be bypassed. So to your questions:
1. That you reconnected the radio w/o the theft circuit & it awoke dashed out says that you will dash out every time you lose power as-is.
2. You need to replace the internal battery. Otherwise you will have to pay $65 reset fee to the dealer every time you've a power interruption. Pay the extra $10 one time.
3. You do not need to pay Becker to change the battery, then pay the dealer to reset. Becker can permanently disable the alarm circuit while they have the radio, so it will come home to you reset & power interruption resistant.
The import fees & paperwork is just a reality of your location v. Becker. I suppose you could drive to Buffalo & mail it & have it sent back to you c/o general delivery at a Buffalo Post Office & drive over the border with it stuffed in the dash, but it's an 8 hour hassle v. some paperwork. For your sanity & enjoyment of the car just deal with it all one time, properly, & be done with it.

Toronto300E

You are absolutely right. After (stupidly) buying the right connectors from Becker Radio in the US for a total of $50 and finding I had this 4 dash and battery problem and finding out Mercedes Toronto wanted $65 to reset the radio and then finding out I would still have to pay probably $150 to ship the radio to Becker Radio in the US I realized that throwing another $215+/- into this radio was crazy. Had I known about all of these issues and their associated extra cost before I ordered the connectors I would have not embarked at all on trying to reinstall this, but before I did it was not clear to me from my research that I would be having these other problems.

Anyway, I ended up buying a Sony CD/Radio (with an Aux Audio In port so I can connect my iPhone/iPod) on sale from Canadian Tire here in Toronto for $92 including tax and will attempt to install it.

As an aside, given the radio was trash anyway, I tried taking it apart to find that damn battery that Becker is not authorized to sell on it's own. I had to pretty well break the radio to look inside but could never find it. The radio has gone to electronics recycling.

Thanks for all the help and comments.

hagar24

Do you still have the connectors from Becker??
I will buy from you.

bill.moore

Years ago when the tiny internal original memory holding battery died I opened the radio, soldiered a 12" long 2 wire pigtail lead and brought it out the back of the radio. To the other end I attached a larger external Lithium 3.6V battery with soldier terminals (available at the time from a local radio/electronics supply store, or search the web now for small industrial batteries), covered the terminals with tape so it wouldn't short out on anything and laid it under the radio behind the ashtray (there is a soft brown matt there) so it would be easily accessible by simply pulling the ashtray out. In that way it could easily be replaced periodically with little trouble. I then went to the local M-B dealer (Vin Devers in Toledo) they took pity on me and reset the radio at no cost. It has worked fine for many years since.

bill.moore

One thing I forgot to mention, when reinstalling the Becker 754 you MUST RECONNECT the single pole anti-theft wire with a spade lug on it BEFORE reinstalling the radio in the dash.

sattarrammo

I think the tool is a UV light pen that erases the EEPROM memory module, I have a 754 that I will be refurbishing myself and update you as I go ( when I start with it )
the original radio was stolen from the car before I bought it, must have been a 780

coderobbie

hello...


I bought a Becker Grand Prix Electronic 754From a oldtimer MB handler.


i connected it to a 12V power supply and then the frontpanel lighted up nicely and the display showed -- -- -- --


it is already 20 hours permanently under 12V but untill now nothing happens.


anybody an idea what to do?


Robert

jeffcruz

I need to remove the Becker 754 radio from my 1987 560 SL. Can anyone help? There are no "key slots" on the bottom edge of this radio.

ALN74

I found a website offering Becker 754 unlock: https://ecu-repair.eu/for-mecedes-be...r-service.html
Has anyone tried it, any luck? I have exactly the same problem.