Effective 21 May 2015, CIC has simplified the process for service workers entering Canada to obtain work permits, if they are coming in to service equipment on which the warranty has expired.
A work permit is still required (unlike warranty service work) and the new employer compliance measures are in place as they are for all LMIA exempt work permits. These are matters that can be arranged quickly though if time is of the essence.
If you want to discuss a specific scenario, please get in touch with our office.