How a Diagnostic Trouble Code (DTC) is Set

When the system detects a problem, the body control module sets a code, but shifts to fail-safe mode, and does not alert the driver to low tire pressures.
If the body control module loses power, or fails, the low tire pressure/TPMS indicator (starts blinking) comes on, but no DTCs are set.
The memory can hold all the DTCs that could possibly be set. However, when the same DTCs are detected more than once, the most recent one overwrites the previous one, so only the latest DTC of each type is stored.
DTCs are indicated in ascending order, not in the order they occurred.
Set DTCs are stored in the EEPROM (nonvolatile memory), and cannot be cleared by disconnecting the 12 volt battery. To clear a DTC, connect the HDS to the data link connector (DLC), and follow the screen prompts.