Detail of 4WD Control System Check
Detail of 4WD Control System CheckStep 1: Malfunction Analysis
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.
Problem symptom confirmation
Check if what the customer claimed in "Customer Questionnaire" is actually found in the vehicle and if that symptom is found, whether it is identified as a failure. (This step should be shared with the customer if possible). Check 4WD control system referring to 2WD/4WD Indicator
Operation Check: Motor-Shift Type and 4WD Control System Operation Inspection: Motor-Shift Type.
DTC check, record and clearance
Perform DTC Check: Motor- Shift Type, record it and then clear it referring to DTC Clearance: Motor-Shift Type. If the malfunction DTC which was once displayed and then cleared cannot be detected (indicated) again when the ignition switch is turned ON, attempt to diagnose the trouble based on the DTC recorded in this step may mislead the diagnosis or make diagnosing difficult. Proceed to Step 2 to check 4WD control module for proper self-diagnosis function. If the malfunction DTC which was once displayed and then cleared can be detected (indicated) again when ignition switch is turned ON, proceed to Step 3.
Step 2: Driving Test
Drive the vehicle at engine speed 2000 rpm or more for 5 minute and check if any trouble symptom (such as indicator flashing) exists. If the malfunction DTC is confirmed again at ignition switch ON, driving test as described is not necessary. Proceed to Step 3.
Step 3: DTC Check
Recheck DTC referring to DTC Check: Motor- Shift Type.
Step 4: Troubleshooting for DTC
According to 4WD Control System Check for the DTC confirmation in Step 3, locate the cause of the trouble, namely in a sensor, switch, wire harness, connector, actuator assembly or other part and repair or replace faulty parts.
Step 5: 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 trouble code recorded in Step 1 to 3.
Step 6: Visual Inspection and 4WD Control System Symptom Diagnosis
Be sure to perform visual check of the items that support proper function of the 4WD control system referring to Visual Inspection: Motor-Shift Type. Check the part of system suspected as a possible cause referring to 4WD Control Symptom Diagnosis:Motor-Shift Type.
Step 7: Final Confirmation Test
Confirm that the problem symptom has gone and the 4WD control system is free from any abnormal conditions. If what has been repaired is related to the malfunction DTC, clear the DTC once and perform test driving and confirm that no DTC is indicated.