Diagnosis and repair workflow
Work Flow
Detailed flow
1.Interview from the customer
Clarify customer complaints before inspection. First of all, perform an interview utilizing stc-20, "diagnostic work sheet" and reproduce symptoms as well as fully understand it. Ask customer about his/her complaints carefully. Check symptoms by driving vehicle with customer, if necessary.
Caution:
Customers are not professional. Never guess easily like “maybe the customer means that...,” Or “maybe the customer mentions this symptom”.
>> Go to 2.
2.Check symptom
Reproduce the symptom that is indicated by the customer, based on the information from the customer obtained by interview. Also check that the symptom is not caused by protection function. Refer to STC-13, "Protection Function".
Caution:
When the symptom is caused by normal operation, fully inspect each portion and obtain the understanding of customer that the symptom is not caused by a malfunction.
>> Go to 3.
3.Perform self-diagnosis
With consult
Perform self-diagnosis.
Is any dtc detected? Yes >> record or print dtc and freeze frame data (ffd). Go to 4.
No >> go to 6.
4.Recheck symptom
With consult
Erase self-diagnostic results.
Perform dtc confirmation procedures for the malfunctioning system.
Note:
If some DTCs are detected at the same time, determine the order for performing the diagnosis based on STC- 14, "DTC Inspection Priority Chart".
Is any dtc detected? Yes >> go to 5.
No >> check harness and connectors based on the information obtained by interview. Refer to gi-39, "intermittent incident".
5.Repair or replace malfunctioning parts
Repair or replace malfunctioning parts
Reconnect part or connector after repairing or replacing.
When dtc is detected, erase self-diagnostic results for “eps”.
>> Go to 7.
6.Identify malfunctioning system by symptom diagnosis
Estimate malfunctioning system based on symptom diagnosis and perform inspection.
Can the malfunctioning system be identified?
Yes >> go to 7.
No >> check harness and connectors based on the information obtained by interview. Refer to gi-39, "intermittent incident".
7.Final check
With consult
Check the reference value for eps control unit.
Recheck the symptom and check that symptom is not reproduced on the same conditions.
Is the symptom reproduced? YES >> GO TO 3.
NO >> Inspection End.
Diagnostic Work Sheet
Description
In general, customers have their own criteria for a problem. Therefore, it is important to understand the symptom and status well enough by asking the customer about his/her concerns carefully. To systemize all the information for the diagnosis, prepare the interview sheet referring to the interview points.
In some cases, multiple conditions that appear simultaneously may cause a dtc to be detected.
Interview sheet sample
Tire labeling
Federal law requires tire manufacturers to
place standardized information on the
sidewall of all tires. This information identifies
and describes the fundamental
characteristics of the tire and also provides
the tire identification number (TIN)
for safety standard certification. The TIN
can b ...
Parking, license plate and tail
lamps are not turned on
Description
The parking, license plate and tail lamps do not turn on in with any lighting
switch setting.
Diagnosis procedure
1.Combination switch (lighting and turn signal switch) inspection
Check the combination switch (lighting and turn signal switch). Refer to
BCS-72, "Symptom Table ...
P0603 ECM
DTC Logic
DTC DETECTION LOGIC
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
Possible cause
P0603
ECM BACK UP CIRCUIT
[Internal control module keep
alive memory (KAM) error]
Malfunction in the internal back up RAM o ...