Found it, Thank You! Like MB Doc said, the horn was behind the right wheel well plastic liner. I was able to replace the offending anti-theft alarm (ATA) horn. By the way, the new part number provided by MB is A219 820 32 26. The old PN was 171 820 25 26. The new part is a little different in design, therefore, you'll need a new 8mm nut to secure it to the horn bracket. Tools needed to do the job includes T-40 & T-30 torks with the 'hole' in the middle, 10mm socket and 13mm wrench for the new nut. The job was straight-forward, took about 30 minutes. Now, my anti-theft alarm is working well again. By the way, the MB guy who sold me the part said the old horns go bad so often on these cars.

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Josemin


88 MB 300E
88 MB 560SEL
99 MB ML 430