Asking for a friend and not seen . Maybe Clarion make. The car battery went flat for some time, and when replaced, the radio would no longer accept the code entry . The 4 dashes would appear but not disappear, one by one on , entering the code , so is now dead. Is there a pair of contact points somewhere inside to do a reset or some procedure like that.
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
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