Verify The Complaint

WARNING: This page is about a different car, the 2008 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.

Make sure the customer's complaint and the service writer's work order description are understood before starting work.
Make sure the correct operation of the system is understood. Read the service article description to verify normal system operation.
Operate the system to see the symptoms. Look for other symptoms that were not reported by the customer, or on the work order, that may be related to the problem.