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Paulwilhelmsen1 · 12-12-2025, 06:05 PM

With a new alternator and regulator installed, the radio works great at 12.2V (battery) but dies quickly (but not immediately) at ~14.4V when the engine is running. The second bit is a major clue to what is wrong. My guess is 1) The internal voltage regulator is dropping a bunch of voltage and gets quite hot 2) after 25 years, either the regulator itself is approaching EOL and/or the heat sink connection is failing. Becker won't give me the schematics for the radio and I am loathe to open the unit up for fear of damaging very old wiring and cables. So, I got a 10A dc to dc (12V out from 8V to 20V in) convertor on Amazon and spliced it between the radio and the car. Voila! Everything works! in the meantime, trying to find a dead unit to disassemble to figure out the voltage regulator part numbers.

Hope this is helpful??

12-12-2025, 06:05 PM	#17
Paulwilhelmsen1 Registered User Join Date: Jul 2025 Location: Sacramento CA Posts: 1	Suspect Its the Radio's Voltage Regulator With a new alternator and regulator installed, the radio works great at 12.2V (battery) but dies quickly (but not immediately) at ~14.4V when the engine is running. The second bit is a major clue to what is wrong. My guess is 1) The internal voltage regulator is dropping a bunch of voltage and gets quite hot 2) after 25 years, either the regulator itself is approaching EOL and/or the heat sink connection is failing. Becker won't give me the schematics for the radio and I am loathe to open the unit up for fear of damaging very old wiring and cables. So, I got a 10A dc to dc (12V out from 8V to 20V in) convertor on Amazon and spliced it between the radio and the car. Voila! Everything works! in the meantime, trying to find a dead unit to disassemble to figure out the voltage regulator part numbers. Hope this is helpful??