A final post script!
Got the new part today for $140, MB dealer price $338!! Get my parts thru my tech so it saves a lot of $$$.
After taking the unit out and replacing with the new amplifier, I could see why the old one failed.
The unit is supposed to have a heat sink plate (3" long x 1.5" wide x 3/16" thick) attached to the bottom. My old unit did not. Also there was no silicon grease applied. So with the missing heat sink plate and no grease it's a wonder that it lasted as long as it did.
Tnx to all you knowledgeable Benz men!
Regards . . . . JimF
'94 S500 Cpe
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