What is the production date on your car? If it is truly a 1990 car then you won't be dealing with a two piece becker radio ( 1432 ). If you cars production date is after 8-89 then it will be a 1991 and will have the 1432 otherwise it will have a becker 1480 that is a conventional radio with the antenna coax behind the radio. The blue wire is the antenna trigger it will have a black vinyl tubing on it and a 1/4 in female spade connector. I will try and check to see if you have any more questions today as I am really familiar with the 124's. Good luck!

Scott@lajollaaudio

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The Mercedes Specialists Since 1986