How to Perform Trouble Diagnoses for Quick and Accurate Repair (Cont'd) - DIAGNOSTIC WORKSHEET
EF & EC-409prose procedureTROUBLE DIAGNOSES
How to Perform Trouble Diagnoses for Quick and Accurate Repair (Cont'd)
DIAGNOSTIC WORKSHEET
There are many kinds of operating conditions that lead to malfunctions on engine components.
A good grasp of such conditions can make trouble-shooting faster and more accurate.
In general, feelings for a problem depend on each customer. It is important to fully understand the symptoms or under what conditions a customer complains.
Make good use of a diagnostic worksheet such as the one shown below in order to utilize all the complaints for trouble-shooting.
| Specification | Value |
|---|---|
| WHATKEY POINTS | Vehicle & engine model |
| WHENKEY POINTS | Date, Frequencies |
| WHEREKEY POINTS | Road conditions |
| HOWKEY POINTS | Operating conditions, Weather conditions, Symptoms |
WHATKEY POINTS
Vehicle & engine model
WHENKEY POINTS
Date, Frequencies
WHEREKEY POINTS
Road conditions
HOWKEY POINTS
Operating conditions, Weather conditions, Symptoms
Worksheet sample
Diagnostic Worksheet Sample
Customer name
Item / OptionsMR/MS
Model & Year
Item / Options
VIN
Item / Options
Engine #
Item / Options
Trans.
Item / Options
Mileage
Item / Options
Incident Date
Item / Options
Manuf. Date
Item / Options
In Service Date
Item / Options
Symptoms / Startability
Item / OptionsImpossible to start; No combustion; Partial combustion; Partial combustion affected by throttle position; Partial combustion NOT affected by throttle position; Possible but hard to start; Others [ ]
Symptoms / Idling
Item / OptionsNo fast idle; Unstable; High idle; Low idle; Others [ ]
Symptoms / Driveability
Item / OptionsStumble; Surge; Detonation; Lack of power; Intake backfire; Exhaust backfire; Others [ ]
Symptoms / Engine stall
Item / OptionsAt the time of start; While idling; While accelerating; While decelerating; Just after stopping; While loading
Incident occurrence
Item / OptionsJust after delivery; Recently; In the morning; At night; In the daytime
Frequency
Item / OptionsAll the time; Under certain conditions; Sometimes
Weather conditions
Item / OptionsNot affected
Weather
Item / OptionsFine; Raining; Snowing; Others [ ]
Temperature
Item / OptionsHot; Warm; Cool; Cold; Humid; °F
Engine conditions
Item / OptionsCold; During warm-up; After warm-up; Engine speed 0 / 2,000 / 4,000 / 6,000 / 8,000 rpm
Road conditions
Item / OptionsIn town; In suburbs; Highway; Off road (up/down)
Driving conditions
Item / OptionsNot affected; At starting; While idling; At racing; While accelerating; While cruising; While decelerating; While turning (RH/LH); Vehicle speed 0 / 10 / 20 / 30 / 40 / 50 / 60 MPH
Check engine light
Item / OptionsTurned on; Not turned on