ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION — Emission-related Diagnostic Information (Cont'd); System Readiness Test (SRT) Code; How to Display SRT Code

CG10, CGA3

ECM. 1st trip freeze frame data is retained in the ECM memory along with the 1st trip 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 ECM memory, 1st trip freeze frame data is no longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the following priorities to update the data.

For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different malfunction is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is stored in the ECM memory, 1st trip freeze data is no longer retained (because only one freeze frame data is stored or 1st trip freeze frame data can be retained in the ECM). If freeze frame data is stored in the ECM memory and freeze frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the ECM memory.

Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM memory is erased. Procedures for clearing the ECM memory are described in "HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION". Refer to EC-7036.

System Readiness Test (SRT) code is specified in Mode 1 of ISO 15031-5/SAE J1979. It indicates whether the self-diagnostic tests for non-continuously monitored items have been completed or not.

Inspection/Maintenance (I/M) tests of the on board diagnostic (OBD) system may become the legal requirements in some states/areas. All SRT codes must be set in this case. Unless all SRT codes are set, conducting the I/M test may not be allowed.

SRT codes are set after self-diagnosis has been performed one or more times. This occurs regardless of whether the diagnosis is in "OK" or "NG", and whether or not the diagnosis is performed in consecutive trips. The following table lists the three SRT items (12 test items) for the ECM used in P11 models.

Together with the DTC, the SRT code is cleared from the ECM memory using the method described later (Refer to EC-7036). In addition, after engine control components/system are repaired or if the battery terminals are removed for more than 1 minute, all SRT codes may be cleared from the ECM memory.

1. With CONSULT-II Selecting "SRT STATUS" in "DTC CONFIRMATION" mode with CONSULT-II. For items whose SRT codes are set, a "CMPLT" is displayed on the CONSULT-II screen; for items whose SRT codes are not set, "INCMP" is displayed as shown below.