Check Mode Procedure

Check mode has a higher sensitivity to malfunctions and can detect malfunctions that normal mode cannot detect. Check mode can also detect all the malfunctions that normal mode can detect. In check mode, DTCs are detected with 1-trip detection logic.

1. Make sure that the items below are true:
   1. Battery positive voltage 11 V or more
   2. Throttle valve fully closed
   3. Transmission in the P or N position
   4. A/C switched OFF
2. Turn the ignition switch OFF.
3. Connect the hand-held tester to the Controller Area Network Vehicle Interface Module (CAN VIM). Then connect the CAN VIM to the Data Link Connector 3 (DLC3).
4. Turn the ignition switch ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II/CHECK MODE.
   Fig 1: Connecting Hand-Held Tester To DLC3

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. Change the ECM to check mode. Make sure the MIL flashes as shown in the illustration.
   NOTE: All DTCs and freeze frame data recorded will be erased if: 1) the hand-held tester is used to change the ECM from normal mode to check mode or vice-versa; or 2) during check mode, the ignition switch is turned from ON to ACC or OFF.
   Before check mode, make notes of the DTCs and freeze frame data.
7. Start the engine. The MIL should turn off after the engine starts.
8. Simulate the conditions of the malfunction described by the customer.
9. After simulating the malfunction conditions, use the hand-held tester diagnosis selector to check the DTC and freeze frame data.

Fig 2: Identifying MIL Blinking Pattern

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002