DTC stands for diagnostic trouble code, a standardized alphanumeric sequence generated by an onboard diagnostic system when it detects a malfunction. The code format usually starts with a letter indicating the system followed by four digits pointing to the specific circuit or component failure. Technicians retrieve these codes using a scan tool to begin their diagnostic process.
Heard on the job
I pulled the DTCs and got a P0300, so we've a random misfire to track down.
Insider tip
A DTC tells you what circuit the computer is unhappy with, not necessarily which part has failed. Never just fire the parts cannon based on a code.
Also heard as
- trouble code
- fault code