Hi, welcome to Just answer
Please tell me complete model number for your Bosch Washing machine
where will the number be?
Inside the door...it starts with E-nr
As you know error code 3 means drain issue...
what you have to do is pull the machine out and then take the back panel off...there is a small plastic square box clipped to the drum, this senses pressure depending on how full the drum is with water...what you have to do is take this box off and clean everything there, also make sure that everything is dried in there...just make sure everything is clean & dried there....let me know how it goes