. General Diagnosis (12 Questions)
Verify driver's complaint, perform visual inspection, and/or road test vehicle; determine needed action.
When a customer brings their vehicle to the shop for repair, they have a concern or problem in their mind but may have difficulty expressing the problem in words. In most repair facilities, it is the service writer's responsibility to help gather information and define the problem so the technician can diagnose it.
Many vehicle concerns can be located with a thorough visual inspection. A leaking fuel pressure regulator diaphragm may cause hard starting and poor mileage complaints. Simply removing the fuel pressure regulator vacuum hose and inspecting for the presence of fuel can isolate the problem without performing detailed fuel system tests. A visual inspection should include checking all air intake plumbing for cracks or loose clamps, checking vacuum hoses conditions, routing and checking spark plug wires for misrouted or damaged cables, checking wiring harnesses for proper routing and for damage from chafing brackets or components on the engine, and also checking all fluids for proper level and condition.
A clear and detailed description of the customer's concerns must be obtained either from the customer or the service writer before diagnostics begin. You should review previous service history of the vehicle supplied by the customer or located in the shop's service records to narrow the scope of your testing.
Performing a road test is part of almost all service routines. A road test allows you to verify a customer concern as well as to verify a successful repair. When test driving a vehicle, you should take note of any unusual noises, look for smoke from the exhaust, operate the vehicle through different speed and load ranges to determine engine and transmission performance, and also pay attention to any steering, suspension, or braking problems that may be evident.
All road test findings should be well...