What is a DTC? Why does an ECU show a DTC? Where can i find a ECU DTC?

What is an ECU DTC?

A DTC stands for Diagnostic Trouble Code. It is a code produced by an engines ECU, to assist in rapid fault correction. ECU's do not use standard DTC and as such each engine manufacturer may have several different sets of codes for different engines.

Where and why are DTC's generated?

The DTC's are generated in the engines ECU. As the engine runs sensors check the engines parameters and when a fault is found a DTC is generated in the ECU, this problem can then be checked and rectified. For this reason ECU's can save significant amounts of time trouble shooting engines, as the ECU can with the help of the DTC point the engineer in the direction of the fault.

How can I read the DTC from the ECU?

For a generator, engines with ECU's fitted are normally used with a generator control module that has the ability to read and display the DTC codes. The generator control module and the ECU communicates on a CANBUS connection. The generator control module reads the code and displays it on the generator controllers screen. Some manufacturers may choose to hide the codes from the user and require a call out to diagnose or view the codes.