As a ServiceMax admin, you have to first determine the exhaustive list of all objects and specific records to which the technician needs access. Then you have to ensure that the technician has the required permissions for those objects and the required records.

You can configure technicians' access to objects, fields, and record types using Salesforce profile permissions and permission sets.

For example, a technician needs to be able to edit a work order to record the details of the work performed, and add/edit/delete Work Detail records to record the parts consumed, labor details, and other expenses incurred. The technician might need read access to the account, contact, and component (Installed Product) related to the scheduled work order and to parts (Product) used to service the work order.

To control technician's access to specific records, you can configure sharing settings in Salesforce.

For instance, the technician needs to have access to all the work orders scheduled for him - you can configure this through sharing based on record ownership. The technician might also need access to work orders not yet assigned to any technician and are possibly assigned to a generic queue. You can configure this using sharing rules.