How to Perform Trouble Diagnoses for Quick and Accurate Repair (Cont'd) — Diagnostic Worksheet
EF & EC-36prose procedureTROUBLE DIAGNOSES
How to Perform Trouble Diagnoses for Quick and Accurate Repair (Cont'd)
DIAGNOSTIC WORKSHEET
KEY POINTS
WHAT ..... Vehicle & engine model
WHEN ..... Date, Frequencies
WHERE ..... Road conditions
HOW ..... Operating conditions, Weather conditions, Symptoms
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.
Worksheet sample
| Field | Options / Details |
|---|---|
| Customer name | MR/MS |
| Model & Year | |
| VIN | |
| Engine # | |
| Trans. | |
| Mileage (kilometer) | |
| Incident Date | |
| Manuf. Date | |
| In Service Date | |
| Symptoms — Startability | ☐ Impossible 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 | ☐ No fast idle ☐ Unstable ☐ High idle ☐ Low idle ☐ Others [ ] |
| Symptoms — Driveability | ☐ Stumble ☐ Surge ☐ Detonation ☐ Lack of power ☐ Intake backfire ☐ Exhaust backfire ☐ Others [ ] |
| Symptoms — Engine stall | ☐ At the time of start ☐ While idling ☐ While accelerating ☐ While decelerating ☐ Just after stopping ☐ While loading |
| Incident occurrence | ☐ Just after delivery ☐ Recently ☐ In the morning ☐ At night ☐ In the daytime |
| Frequency | ☐ All the time ☐ Under certain conditions ☐ Sometimes |
| Weather conditions — Weather | ☐ Not effected ☐ Fine ☐ Raining ☐ Snowing ☐ Others [ ] |
| Weather conditions — Temperature | ☐ Hot ☐ Warm ☐ Cool ☐ Cold ☐ Humid °F |
| Engine conditions | ☐ Cold ☐ During warm-up ☐ After warm-up Engine speed scale: 0 — 2,000 — 4,000 — 6,000 — 8,000 rpm |
| Road conditions | ☐ In town ☐ In suburbs ☐ Highway ☐ Off road (up/down) |
| Driving conditions | ☐ Not affected ☐ At starting ☐ While idling ☐ At racing ☐ While accelerating ☐ While cruising ☐ While decelerating ☐ While turning (RH/LH) Vehicle speed scale: 0 — 10 — 20 — 30 — 40 — 50 — 60 MPH |
| Check engine light | ☐ Turned on ☐ Not turned on |
Customer name
Options / DetailsMR/MS
Model & Year
Options / Details
VIN
Options / Details
Engine #
Options / Details
Trans.
Options / Details
Mileage (kilometer)
Options / Details
Incident Date
Options / Details
Manuf. Date
Options / Details
In Service Date
Options / Details
Symptoms — Startability
Options / Details☐ Impossible 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
Options / Details☐ No fast idle ☐ Unstable ☐ High idle ☐ Low idle ☐ Others [ ]
Symptoms — Driveability
Options / Details☐ Stumble ☐ Surge ☐ Detonation ☐ Lack of power ☐ Intake backfire ☐ Exhaust backfire ☐ Others [ ]
Symptoms — Engine stall
Options / Details☐ At the time of start ☐ While idling ☐ While accelerating ☐ While decelerating ☐ Just after stopping ☐ While loading
Incident occurrence
Options / Details☐ Just after delivery ☐ Recently ☐ In the morning ☐ At night ☐ In the daytime
Frequency
Options / Details☐ All the time ☐ Under certain conditions ☐ Sometimes
Weather conditions — Weather
Options / Details☐ Not effected ☐ Fine ☐ Raining ☐ Snowing ☐ Others [ ]
Weather conditions — Temperature
Options / Details☐ Hot ☐ Warm ☐ Cool ☐ Cold ☐ Humid °F
Engine conditions
Options / Details☐ Cold ☐ During warm-up ☐ After warm-up Engine speed scale: 0 — 2,000 — 4,000 — 6,000 — 8,000 rpm
Road conditions
Options / Details☐ In town ☐ In suburbs ☐ Highway ☐ Off road (up/down)
Driving conditions
Options / Details☐ Not affected ☐ At starting ☐ While idling ☐ At racing ☐ While accelerating ☐ While cruising ☐ While decelerating ☐ While turning (RH/LH) Vehicle speed scale: 0 — 10 — 20 — 30 — 40 — 50 — 60 MPH
Check engine light
Options / Details☐ Turned on ☐ Not turned on