3C
4WD Control System Check
WARNING:
• When shifting transfer from 2H to 4H with vehicle lifted, a hard impact occurs due to the speed difference between transfer output front shaft and transfer output rear shaft.
The impact may damage transfer system and vehicle may fall from lifting device, resulting in personal injury.
• Be sure to depress brake pedal fully (tire stops completely) whenever shifting transfer from 2H to 4H with vehicle lifted.
Refer to the following items for the details of each step.
Step Action YES NO
1
icon  Customer complaint analysis
1) Perform customer complaint analysis.
Was customer complaint analysis performed?
Go to step 2.
Perform customer complaint analysis.
2
icon  DTC check, record and clearance
1) Check for DTC.
Is there any DTC(s)?
Write them down and clear them by referring to DTC Clearance . Go to Step 3.
Go to Step 4.
3
icon  Visual inspection
1) Perform visual inspection.
Is there any faulty condition?
Repair or replace malfunction part. Go to Step 11.
Go to Step 5.
4
icon  Visual inspection
1) Perform visual inspection.
Is there any faulty condition?
Repair or replace malfunction part. Go to Step 11.
Go to Step 8.
5
icon  Trouble symptom confirmation
1) Shift transfer to “2H”, “4H” and “4L” positions referring to 4WD Control System Operation Inspection .
2) Confirm trouble symptom.
Is trouble symptom identified?
Go to Step 6.
Go to Step 7.
6
icon  Rechecking and record of DTC
1) Recheck for DTC referring to DTC Check .
Is there any DTC(s)?
Go to Step 9.
Go to Step 8.
7
icon  Rechecking and record of DTC
1) Recheck for DTC referring to DTC Check .
Is there any DTC(s)?
Go to Step 9.
Go to Step 10.
8
icon  4WD control symptom diagnosis
1) Check and repair according to 4WD Control Symptom Diagnosis .
Are check and repair complete?
Go to Step 11.
Check and repair malfunction part(s). Go to Step 11.
9
icon  Troubleshooting for DTC
1) Check and repair according to applicable DTC flow.
Are check and repair complete?
Go to Step 11.
Check and repair malfunction part(s). Go to Step 11.
10
icon  Check for intermittent problems
1) Check for intermittent problems.
Is there any faulty condition?
Repair or replace malfunction part(s). Go to Step 11.
Go to Step 11.
11
icon  Final confirmation test
1) Clear DTC if any.
2) Perform final confirmation test.
Is there any problem symptom, DTC or abnormal condition?
Go to Step 6.
End.
Detail of 4WD Control System Check
Step 1: Customer complaint analysis
Record details of the problem (failure, complaint) and how it occurred as described by the customer.For this purpose, use of such a questionnaire form as shown in the following will facilitate collecting information to the point required for proper analysis and diagnosis.
Customer questionnaire (Example)
NOTE:
The form is a standard sample. It should be modified according to conditions characteristic of each market.
Step 2. DTC check, record and clearance
Check DTC first, referring to DTC Check . If DTC exists, write down DTC and then clear malfunction DTC(s) by referring to DTC Clearance . Malfunction DTC indicates malfunction in the system but it is not possible to know from it whether the malfunction is occurring now or it occurred in the past and normal condition has been restored. In order to know that, check symptom in question according to Step 5 and then recheck DTC according to Step 6.
Diagnosing a trouble based on the DTC in this step only or failure to clear the DTC in this step may result in a faulty diagnosis, trouble diagnosis of a normal circuit or difficulty in troubleshooting which is otherwise unnecessary.
Step 3 and 4. Visual inspection
As a preliminary step, be sure to perform visual check of the items that support proper function of the 4WD control system referring to Visual Inspection
Step 5. Trouble symptom confirmation
Check trouble symptoms based on information obtained in Step 1: Customer complaint analysis and Step 2. DTC check, record and clearance . Also, reconfirm DTC according to “DTC Confirmation Procedure” described in each DTC flow.
Step 6 and 7. Rechecking and record of DTC
Refer to DTC Check for checking procedure.
Step 8. 4WD control symptom diagnosis
Check the parts of the system suspected as a possible cause referring to 4WD Control Symptom Diagnosis .
Step 9. Troubleshooting for DTC
Based on the DTC indicated in Step 6 / 7 and referring to “applicable DTC flow”, locate the cause of the trouble, namely in a sensor, switch, wire harness, connector, actuator, 4WD control module or other part and repair or replace faulty parts.
Step 10. Check for intermittent problem
Check parts where an intermittent trouble is easy to occur (e.g. wire harness, connector, etc.), referring to Intermittent and Poor Connection Inspection and related circuit of DTC recorded in Step 2.
Step 11. Final confirmation test
Confirm that the problem symptom has gone and the vehicle is free from any abnormal conditions. If what has been repaired is related to the malfunction DTC, clear the DTC once and check to ensure that no malfunction DTC is indicated.