Well, whether they 'sticky' or have a bad connection at the connector, removing the IC will tell the story. Since the newer cars like yours have a ribbon cable (not separate connections), the meters are most likely 'sticky'.
If you take it out completely, it pretty simple to take the IC apart. Then you can properly diagnose the two meters.
I would then definitely replace all lamps. Mine just plug in and are housed in a plastic base. Your's have got to be similar.
Regards . . . . JimF
'94 S500 Cpe
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