Oh your lovely beautiful orange 240D! Sounds like the water pump seized causing the belt to seize and therefor stopping the power steering, especially with the loss of coolant.

Verify what pulley seized, probably the water pump. Replace the pump, belt and be on your way! Good job sir for not cooking the engine and pulling over ASAP.

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1976 Mercedes 240D (Sold)
1985 Mercedes 300D Turbo Diesel: 500,000KM
1986 Mercedes 300E (Sold)
1988 Mercedes 300E (Sold)
2002 Mercedes C240 (Sold)
2008 Mercedes C350 4matic

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