The instrument cluster is at irregular intervals

Hello Together The instrument cluster of my Volvo C70 Cabriolets (2001) is sporadically off (tacho failure, KM display missing), STC/ABS/warning light and occasionally motor control light are on. Most of the time after a few minutes drive the tacho and KM counters work again and the indicator lights go off, only STC always stays on until the engine is switched off. When reading out different diagnostic devices each indicate the error P1633 (Accelera. Pedal Pos. Sensor 2 Signal too Low). My guess was with the defect of the el. gas pedal, after I changed it already for a new original part, unfortunately the error occurred again. Does someone have an idea where the real problem lies? Best regards Sebastian