Can a bad solenoid cause my transmission not to work or my vehicle to go in gear

Sure, "a solenoid" is an electrical component that actuates action inside the transmission. So, if it's "bad" then there will certainly be a malfunction of the transmission operation. Trouble is - there are many possible causes of the transmission not going into gear. Hands on testing is required to find out what is happening with the transmission and what the best solution is. These 5R55 transmissions can have valve body issues - which is where the solenoids connect to.. It's all a wild guess until you get data from a diagnostic tool related to transmission commands and response to those commands. www.repairpal.com/repair-shops