DTC and Freeze Frame Data

DIAGNOSIS SYSTEM (HPCM)

DIAGNOSIS DESCRIPTION : DTC and Freeze Frame Data


DTC AND 1ST TRIP DTC

The following shows 2nd trip detection diagnosis that illuminates the MIL.
The 1st trip DTC number is the same as the DTC number.
If a malfunction is detected during the 1st trip, the 1st trip DTC is saved in the HPCM memory. At this time, the
MIL does not illuminate. Some of the diagnoses illuminate the hybrid system warning lamp and/or the 12-volt battery charge warning lamp, and other diagnoses do not illuminate them.
If the same malfunction is not detected in the 2nd trip (meeting the required driving pattern), the 1st trip DTC is cleared from the HPCM memory. If the same malfunction is detected in the 2nd trip, both the 1st trip DTC and
DTC are saved in the HPCM memory and the MIL, the hybrid system warning lamp, and/or the 12-volt battery charge warning lamp illuminate.
The procedure for erasing the DTC and the 1st trip DTC from HPCM memory is described in "How to Erase
DTC and 1st Trip DTC" in Hybrid Powertrain Control Module.
Testing and Inspection for the malfunctions for which the 1st trip DTC is displayed.
1st trip DTC is specified in Service $07 of SAE J1979/ISO 15031-5.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame data as specified in Work Flow procedure Step 2, Flowchart of Trouble Diagnosis.
Then perform DTC Confirmation Procedure or Component Function Check to try to duplicate the malfunction.
If the malfunction is duplicated, the item requires repair.

FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA

The HPCM records the driving conditions such as hybrid system condition when a malfunction is detected.
Data which are stored in the HPCM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT screen.
HPCM can store three sets of freeze frame data (one set for MIL-illuminating DTC and two sets for non-MIL illuminating DTC). 1st trip freeze frame data is stored in the HPCM memory along with the 1st trip DTC.
For MIL-illuminating DTC, there is no priority for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once freeze frame data (2nd trip detection/MIL on) is stored in the
HPCM memory, 1st trip freeze frame data is no longer stored. Remember, only one set of freeze frame data can be stored in the HPCM.
For non-MIL-illuminating DTC, the freeze frame data of the 1st trip DTC has no priority. Every time another 1st trip DTC is detected after two freeze frame data of the 1st trip DTC are stored, the older freeze frame data is updated. However, once freeze frame data (2nd trip detection/MIL on) is stored in the HPCM memory, 1st trip freeze frame data is no longer stored. Remember, only one set of freeze frame data can be stored in the
HPCM.
The HPCM has the following priorities to update the data.





Both 1st trip freeze frame data and freeze frame data (along with the DTC) are cleared when the HPCM memory is erased. For the procedure for erasing the HPCM memory, refer to "How to Erase DTC and 1st Trip DTC"
of Hybrid Powertrain Control Module.