If you are married and living together (even if not living together) may I ask why you are not filing a Joint return? It is usually better to file Joint. Joint has the lowest tax rates and the highest Standard Deduction. You can lose several credits filing MFS. And if you are in a Community Property state MFS gets tricky to figure out.
Yes you can claim him, it doesn't matter how much he makes if he is under 19 or under 24 and full time student. Be sure on his return he checks the box that says someone else can claim you. Who can you claim
https://ttlc.intuit.com/community/credits-and-deductions/help/who-can-i-claim-as-my-dependent/01/267...
And why is he tax exempt? Most people aren't. Just because he has a low income does not make him tax exempt.
