Automatic Transmission Diagnostic Flow Chart

AUTOMATIC TRANSMISSION DIAGNOSTIC FLOW CHART





Refer to the following for the details of each 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 inspection form will facilitate collecting information to the point required for proper analysis and diagnosis.

2. DIAGNOSTIC TROUBLE CODE (DTC)/FREEZE FRAME DATA CHECK, RECORD AND CLEARANCE
First, referring to DTC check section, check DTC (including pending DTC). If DTC exists, print or write down DTC and freeze frame data and then clear them by referring to DTC clearance section. 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 4 and then recheck DTC according to Step 5.

Diagnosing a trouble based on the DTC in this step only or failure to clear the DTC in this step may result in an faulty diagnosis, trouble diagnosis of a normal circuit or difficulty in troubleshooting which is otherwise unnecessary.

3. VISUAL INSPECTION
As a preliminary step, be sure to perform visual check of the items that support proper function of the A/,T and engine referring to Visual Inspection section

4. TROUBLE SYMPTOM CONFIRMATION
Check trouble symptoms based on information obtained in Step 1 "CUSTOMER COMPLAINT ANALYSIS" and Step 2 "DTC/FREEZE FRAME DATA CHECK".
Also, recheck DTC according to "DTC Confirmation Procedure" described in each "DTC FLOW CHART".

5. RECHECKING AND RECORD OF DTC/FREEZE FRAME DATA
Refer to "DTC check" section for checking procedure.

6. A/T BASIC CHECK AND TROUBLE DIAGNOSIS TABLE
Perform A/T basic check according to the "A/T Basic Check Flow Chart" first. When the end of the flow chart has been reached, check the parts of the system suspected as a possible cause referring to TROUBLE DIAGNOSIS TABLE and based on symptoms appearing on the vehicle (symptoms obtained through steps of customer complaint analysis, trouble symptom confirmation and/or A/T basic check) and repair or replace faulty parts, if any.

7. DIAGNOSTIC TROUBLE CODE FLOW CHART
Based on the DTC indicated in Step 5 and referring to "DIAGNOSTIC TROUBLE CODE FLOW CHART", locate the cause of the trouble, namely in a sensor, switch, wire harness, connector, actuator, PCM or other part and repair or replace faulty parts.

8. 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" and related circuit of DTC recorded in Step 2.

9. FINAL CONFIRMATION TEST
Confirm that the problem symptom has gone and the A/T is free from any abnormal conditions.
If what has been repaired is related to the malfunction DTC, clear the DTC once, set conditions under which DTC was detected and A/T and/or vehicle was repaired and confirm that no DTC is indicated.