Vehicle Code 40509.5 is the process where the court informs DMV that a person has failed to pay fines or appear for a court date.
The court issues the hold and sends notice to DMV, which mails a notice saying you have 30 days to correct the problem or your license will be suspended. The 30 days starts when DMV mails the notice.
If you received the DMV notice and the deadline has passed, his license is suspended. He can check with DMV to see if the license has been suspended yet. That isn't supposed to happen if you didn't receive the 30-day notice... but it's better to check first to see if your license is valid. It will avoid getting arrested, hauled to jail and having your car towed.
You must deal with this ASAP. An attorney can get the 40509.5 hold lifted fairly quick and find out what the violation is for. Is this in the Chatsworth Court? Call me to discuss further.
Sounds like your husband needs to go into court and deal with his court issues. Once he does that, he should receive an "abstract of judgment"...with that he can go to the DMV and deal with his issues. You should probably hire an attorney to make sure that everything is dealt with properly.