Read and clear faults

Fault memory is read over the same session as parameters. Save the table before clearing it.

Read

• ECU List → Read DTC reads current faults from every ECU.
• Read DTC List reads the codes the ECU supports, whether or not they are stored.
• In ECU Edit → DTC, the header shows the DTC format, supported flags and the number of stored codes.

Snapshot data

Expand the snapshot section under a code to see the values recorded when the fault was set. The fields come from the project dtc_snapshot_data template. If a field has no description, the raw value is shown instead of a guess.

Status colours

• Red — Active.
• Blue — Stored.
• Green — Not Active.

The colour is a UI hint, not a replacement for the status byte. The raw status is available in the log.

Clear

• ECU List → Clear DTC clears every ECU in the project.
• ECU Edit → DTC → Clear DTC clears one ECU.
• Clearing is a write operation and asks for confirmation.

Before clearing, save a project dump (ECU List → Save/Load → Save Data) or export the ECU table to CSV. A cleared fault is gone unless it is still active and returns on the next driving cycle.

Descriptions

• Global database: <workspace>/data/dtc/codes.json or .txt.
• Project-local database: Project Properties → Local DTC File (.json or .txt).
• JSON uses a codes map; TXT uses one CODE description line per code. Lines starting with # or ; are ignored.
• Codes may be P, C, B or U followed by 5 or 7 hex characters.
• If a code has no description, the code is still read and exported; only the text is missing.

A missing DTC file is highlighted in red in Project Properties.

Related

• Diagnostics and DTC
• Read and write values
• File formats