How To Use OEM Diagnostic Procedures
^ VEHICLE BROUGHT TO SHOP ^1. Fill out Customer Problem Analysis Check Sheet found under Procedures.
2. Check and clear diagnostic trouble codes as described under Computers and Control Systems Testing Procedures. Testing and Inspection
3. Set up the diagnostic test mode. For information refer to Setting and Using Test Mode, under Computers and Control Systems / How To Display And Read Diagnostic Trouble Codes. Testing and Inspection
4. Problem symptom confirmation (Does the malfunction occur?)
^ YES - Go to step 6.
^ NO - Go to step 5.
5. Symptom simulation as described in the Problem Confirmation Test.
6. Diagnostic trouble code check. For help, refer to Computers and Control Systems Testing Procedures. Testing and Inspection
^ Normal Code Is Output - Go To Step 7.
^ Malfunction Code Is Output - Go To appropriate Trouble Code Chart.
Testing and Inspection
7. Perform Basic Inspection Procedures.
^ If problems are found, continue troubleshooting as described in Checking the Basics.
^ If problems are not found during the Basic Inspection, proceed to step 8.
8. Use the diagnostic matrix chart under Diagnosis By Symptom and proceed with component or circuit inspections as indicated.
^ If no problems are identified using these procedures proceed to step 9.
9. Check For momentary interruption as described in the Problem Confirmation Test.
^ If diagnostic trouble codes are found using the Problem Confirmation Test, go to the indicated trouble code chart under Computers and Control Systems Diagnostic Charts. Testing and Inspection
^ If problem symptoms are confirmed with the Problem Confirmation Test, go to the diagnostic matrix chart under Diagnosis by Symptom.
10. Identification of problem.
^ When the problem source has been isolated, perform repairs, adjustments or replace components as indicated. Then proceed to step 11.
11. Following repairs or adjustments always roadtest vehicle to confirm repair.
^ END ^