Agree with David. . .
check your fans: let it idle in the driveway with hood down, a/c OFF, etc. When the temp gauge shows around 100C, the fans should come on.
With the A/C on, the fans should start almost immediately if the car is 'warm' (80C or higher). The pressure switch should cause the fans to turn on.
Do a search for related articles on the subject.
Regards . . . . JimF
'94 S500 Cpe
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