FYI, Diagnosing cost is already included on your bill as
hourly labor and if not, they’ll charge separately.
And as of electrical problems,
Usually, it’s a circuit short problem but it’s not an
easy job to find out where it happened.
And, maybe it’s more difficult to find a good mechanic to
handle electric problem. Personally, I haven’t seen one yet.
Check your bulbs, relays, fuses first and also check if there’s
any peeled off area on your electric cable surfaces.