This is usually caused by some component overheating and this then causes the unit to shut off. often in the power supply, or indeed even the laser head assembly, itself.
And in my professional recommendation, you should get a "Quote" for repair, from, an, Approved Service Center. Now, this point is very important for a good result, Always contact, their "Local" or a, "Head Office" Broksonic, in your case. Ask them, for a referral to an authorised servicing center, where you ask for a "Quote". Now, when you get the information you want, then you can decide as to repair of replacement.
The reason we want an approved agent, is that way, all the engineers are trained on their own brand sets, they have seen almost all faults, and will get the job done quicker, and for less cost, and usually have parts on hand, also sometimes, there has been a service bulletin in issued and the repair may be subsided or even free. There are many, many, many reasons that will display this symptom though, apart from the initially mooted problem, and one must work through the troubleshooting steps to isolate and identify, the Cause and repair that and any damage done.