Engine Control System Self-Diagnostics: Other Toyota Corolla IX

TWO-TRIP DETECTION LOGIC

Note. When road testing vehicle in CHECK mode (Toyota hand-held tester only), two-trip detection logic will not function. Also, MIL will illuminate first time a malfunction is detected.

When a malfunction initially occurs, Diagnostic Trouble Code (DTC) will be temporarily stored in ECM memory, but MIL on instrument panel will not illuminate. The second time malfunction is detected, MIL on instrument panel will illuminate, provided ignition is turned off and then back on after first malfunction was detected. This is referred to as "Two-Trip Detection Logic" and only applies to specific DTCs.

DATA LINK CONNECTOR

OBD-II regulations (SAE J-1962) standardizes Data Link Connector (DLC) configurations. DLC is located under left side of instrument panel, left of steering column. (Scheme 70)

Scheme 70

FREEZE FRAME DATA

OBD-II scan tool or Toyota hand-held tester can by used to check freeze frame data. ECM records engine operating condition when a misfire, fuel trim (mixture) malfunction or other malfunction (fuel system, calculated load, coolant temperature, fuel trim (mixture), engine speed, vehicle speed, etc.) exists. If more than one DTC is detected, only data from the first malfunction is recorded. Recorded data is useful for determining conditions during which the malfunction occurred.

NORMAL Mode Code Retrieval

1. Connect scan tool to Data Link Connector (DLC) No. 3. (Scheme 70) Turn ignition on with engine off. Turn scan tool on. Using scan tool manufacturer's instructions, check for DTCs and freeze frame data.
2. If scan tool displays UNABLE TO CONNECT TO VEHICLE, check DLC No. 3. See «DATA LINK CONNECTOR NO. 3 INSPECTION»(ref-133205-S19278998092002021900000) under SCAN TOOL PROBLEMS. If scan tool does not display UNABLE TO CONNECT TO VEHICLE, go to next step.
3. Record any DTCs and freeze frame data displayed for system diagnosis. If driveability problem exists and no DTCs are present, go to «TROUBLE SHOOTING - NO CODES»(ref-133220) article for diagnosis by symptom.
4. If any DTCs are present, perform appropriate DTC test under DIAGNOSTIC TESTS. For DTC descriptions, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-133205-S01067858722002021900000) table under DIAGNOSTIC TROUBLE CODE DEFINITIONS. For more information on freeze frame data, see «FREEZE FRAME DATA»(ref-133205-S36503079612002021900000). For information on two-trip detection logic DTCs, see «TWO-TRIP DETECTION LOGIC»(ref-133205-S24776407542002021900000).
5. After repairs have been completed, clear DTCs from ECM. See «CLEARING DIAGNOSTIC TROUBLE CODES»(ref-133205-S09622218542002021900000). Road test vehicle to ensure all symptoms and/or complaints have been repaired.

CHECK Mode Code Retrieval (Toyota Hand-Held Tester Only)

Note. If ignition switch is turned from ON to ACC or OFF position during CHECK mode, all DTCs and freeze frame data will be erased. DO NOT switch modes until all DTCs and freeze frame data are recorded.

1. Ensure vehicle battery is fully charged. Apply parking brake. Shift transmission/transaxle into Neutral (M/T) or Park (A/T). Turn A/C and all accessories off. Ensure throttle valve is fully closed. Turn ignition off. Connect scan tool to Data Link Connector (DLC) No. 3. (Scheme 70) Turn ignition on with engine off. Turn scan tool on.
2. Switch scan tool from NORMAL mode to CHECK mode. CHECK mode is operational if MIL on instrument cluster flashes. Start engine. If no DTCs are present, MIL will turn off. Try to simulate conditions of driveability complaint described by customer.
3. Record any DTCs and freeze frame data displayed for system diagnosis. If driveability problem exists and no DTCs are present, go to «TROUBLE SHOOTING - NO CODES»(ref-133220) article for diagnosis by symptom.
4. If any DTCs are present, perform appropriate DTC test under «DIAGNOSTIC TESTS»(ref-133205-S26089490592002021900000). For DTC description, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-133205-S01067858722002021900000) table under DIAGNOSTIC TROUBLE CODE DEFINITIONS. For more information on freeze frame data, see «FREEZE FRAME DATA»(ref-133205-S36503079612002021900000). For information on two-trip detection logic DTCs, see «TWO-TRIP DETECTION LOGIC»(ref-133205-S24776407542002021900000).
5. After repairs for DTC have been completed, DTC must be cleared from ECM memory. See «CLEARING DIAGNOSTIC TROUBLE CODES»(ref-133205-S09622218542002021900000). Road test vehicle to ensure all symptoms and/or complaints have been repaired.

SUMMARY

If no Diagnostic Trouble Codes (DTC) are present and a no start condition exists, proceed to BASIC DIAGNOSTIC PROCEDURES - 4-CYLINDER article. If no DTCs are present and a driveability symptoms exist or intermittents exist, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, ENGINE STALLS, etc.) or intermittent procedures.