DTC Management Services¶

ClearDiagnosticInformation (0x14)¶

Clear stored DTCs by group.

Byte	Field	Value	Description
0	SID	0x14	Service identifier
1–3	groupOfDTC	3 bytes	DTC group or `FF FF FF`

Byte	Field	Value	Description
0	SID	0x54	Positive response

NRC	Meaning
0x22	conditionsNotCorrect
0x31	requestOutOfRange

None.

Default, Extended.

from pyudskit import UDS
uds = UDS()
print(uds.clear_dtcs()["uds_bytes"])  # 14 FF FF FF

Data loss

Clearing DTCs also clears related freeze frame data.

Read DTCs, status, snapshot data, and extended records.

Byte	Field	Value	Description
0	SID	0x19	Service identifier
1	subFunction	0x01–0x15	Report type
2–N	parameters	bytes	Subfunction parameters

Byte	Field	Value	Description
0	SID	0x59	Positive response
1	subFunction	echo	Echo of request
2–N	data	bytes	DTC data

NRC	Meaning
0x13	incorrectMessageLengthOrInvalidFormat
0x31	requestOutOfRange
0x22	conditionsNotCorrect

SubFunction	Name
0x01	reportNumberOfDTCByStatusMask
0x02	reportDTCByStatusMask
0x03	reportDTCSnapshotIdentification
0x04	reportDTCSnapshotRecordByDTCNumber
0x05	reportDTCExtDataRecordByDTCNumber
0x06	reportNumberOfDTCBySeverityMaskRecord
0x07	reportDTCBySeverityMaskRecord
0x08	reportSeverityInformationOfDTC
0x09	reportSupportedDTC
0x0A	reportAllSupportedDTC
0x0B	reportFirstTestFailedDTC
0x0C	reportFirstConfirmedDTC
0x0D	reportMostRecentTestFailedDTC
0x0E	reportMostRecentConfirmedDTC
0x0F	reportMirrorMemoryDTCByStatusMask
0x10	reportMirrorMemoryDTCExtDataRecordByDTCNumber
0x11	reportNumberOfMirrorMemoryDTCByStatusMask
0x12	reportNumberOfEmissionsRelatedOBDDTCByStatusMask
0x13	reportEmissionsRelatedOBDDTCByStatusMask
0x14	reportDTCFaultDetectionCounter
0x15	reportDTCWithPermanentStatus

Default, Extended.

from pyudskit import UDS
uds = UDS()
print(uds.read_dtcs(0x08)["uds_bytes"])  # 19 02 08

Large responses

DTC lists can exceed single-frame limits. Use a transport that supports multi-frame responses.