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Detecting and Storing Diagnostic Trouble Codes (DTCs)

When the Generic Electronic Module (GEM) energizes an external device, a short circuit condition can momentarily exist. This fault is not immediately stored as a Diagnostic Trouble Code (DTC) since the fault can disappear after a few milliseconds. The GEM repeatedly attempts to energize the device for one second to confirm that the fault still exists.

If the device is successfully energized before one second elapses, a DTC is not stored and fault management action is not taken. If the fault continues after the predetermined fault time, a DTC is stored and appropriate fault management action is then taken.