Engine Diagnostic Flow Chart

Steps 1 - 11:

Refer to the following items for the details of each step.

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 an inspection form will facilitate collecting information to the point required for proper analysis and diagnosis.

NOTE: The form is a standard sample. It should be modified according to conditions characteristic of each market.

Step 2: DTC / Freeze Frame Data Check, Record and Clearance
First, check DTC (including pending DTC), referring to "DTC Check", Reading Diagnostic Trouble Codes. If DTC is indicated, print it and freeze frame data or write them down and then clear them by referring to "DTC Clearance: J18 Engine". DTC indicates malfunction that occurred in the system but does not indicate whether it exists now or it occurred in the past and the normal condition has been restored now. To check which case applies, check the symptom in question according to Step 4 and recheck DTC according to Step 6 and 7. Attempt to diagnose a trouble based on DTC in this step only or failure to clear the DTC in this step will lead to incorrect diagnosis, trouble diagnosis of a normal circuit or difficulty in troubleshooting.

NOTE:
- If only DTC P0461 (Fuel level sensor circuit performance problem) is indicated in this step, perform visual inspection according to Step 3 and then proceed to "DTC P0461: Fuel Level Sensor (Gauge) Circuit Performance Problem: J18 Engine".
- If only Automatic transmission DTCs (P0705 to P1895) are indicated in this step, perform trouble diagnosis according to "DTC Table: "for A/T.

Step 3 and 4: Visual Inspection (See Visual Inspection of Diagnosis in This Section)
As a preliminary step, be sure to perform visual check of the items that support proper function of the engine referring to "Engine System Check: J18 Engine".

Step 5: Trouble Symptom Confirmation
Based on information obtained in Step 1: Customer complaint analysis and Step 2: DTC / freeze frame data check, confirm trouble symptoms. Also, reconfirm DTC according to "DTC Confirmation Procedure" described in each DTC flow.

Step 6 and 7: Rechecking and Record of DTC / Freeze Frame Data
Refer to "DTC Check", Reading Diagnostic Trouble Codes "DTC Check" (for ECM) for checking procedure.

Step 8: Engine Basic Inspection and Engine Symptom Diagnosis
Perform basic engine check according to the "Engine Basic Inspection: J18 Engine" first. When the end of the flow has been reached, check the parts of the system suspected as a possible cause referring to "Malfunction Indicator Lamp (MIL) Check" and based on symptoms appearing on the vehicle (symptoms obtained through steps of customer complaint analysis, trouble symptom confirmation and/or basic engine check) and repair or replace faulty parts, if any.

Step 9: DTC Flow (See each DTC diag. flow)
Based on the DTC indicated in Step 6 or 7 and referring to the applicable DTC diag. flow, locate the cause of the trouble, namely in a sensor, switch, wire harness, connector, actuator, ECM 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 engine is free from any abnormal conditions. If what has been repaired is related to the DTC, clear the DTC once, perform DTC confirmation procedure and confirm that no DTC is indicated.