It sounds like a goofy PBU, and they certainly do that. But it also sounds like the control unit thinks the temperature in the car is lower than what it actually is. It's been 11 years since I owned a 124, so I'm asking - is it possible that you have an unwanted path from the cold air duct to the temperature sensor?

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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