I have an individual interested in my '93 300D. He resides in a northern region of the U.S. and asked me if this model came with a block heater as standard equipment. Thought I would put the question out to forum members more familiar with the original specifications of the W124 model than this scribe.
I have looked on both sides of the block (that are visible with the aid of a flashlight) and could not identify a "tell tale" block heater element with a plug end. I am quite certain that the car does not have the familiar power cord but this may not preclude the motor from having the aforementioned block heater element/expansion plug.

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'82 300D Turbo 204K
'10 Toyota Prius 85K
'13 AMG C63 (P30) 23K
'14 Audi Q5 TDI 46K
'16 RAM 2500 CTD 12K

'10 VW Jetta TDI 65K (traded)
'12 Nissan Leaf 34K (returned end of lease)
'15 Audi A6 TDI 25K (traded)
'95 E320 166K (traded)
'93 300D 2.5 Turbo 168K (sold)