DTCM - Pre-Diagnostic Troubleshooting Procedure: Notes

For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS article  .

Perform the following pre-diagnostic troubleshooting procedures prior to performing any diagnostic test. 

Always perform diagnostics with a fully charged battery to avoid false symptoms.

1. With the scan tool, read ABS DTCs. If ABS DTCs are present, perform to the appropriate diagnostic procedure(s) before proceeding. Refer to DIAGNOSTIC CODE INDEX .
2. Check the vehicles repair history.
3. If the vehicle has a repair history that pertains to the customer's current complaint, review the repair.
4. Check for any TSBs related to the customer's complaint.
5. Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
6. With the scan tool, read the DTCM DTCs. Record all Stored, Active, and Pending DTC information. Diagnose any pending DTC as a matured DTC.
7. Use the wiring diagram as a guide, inspect the fuses, wiring and connectors related to this circuit and repair as necessary.
8. Refer to the When Monitored and Set Conditions for this DTC. DTCs can set at ignition on, at start up, driving under specific conditions, and after controller diagnostic monitors have run or otherwise known as a Good Trip.
9. Check for any Service Information Tune-ups or Service Bulletins for any possible causes that may apply. Check for controller software update information. Some conditions can be corrected by upgrading the Engine (PCM) controller software.