HINT:

Hand-held tester only:

Compared to normal mode, check mode is more sensitive to malfunctions. Therefore, check mode can detect the malfunctions that cannot be detected by normal mode.

NOTE: All the stored DTCs and freeze frame data are erased if: 1) the ECM is changed from normal mode to check mode or vice versa; or 2) the ignition switch is turned from on (IG) to on (ACC) or off while in check mode.
Before changing modes, always check and make a note of any DTCs and freeze frame data.

CHECK MODE PROCEDURE (Using a hand-held tester)
1. Check and ensure the following conditions:
  1. Battery voltage 12 V or more
  2. Throttle valve fully closed
  3. The shift lever is in the P or N position
  4. A/C switched OFF
2. Turn the ignition switch off.
3. Connect a hand-held tester to the DLC3.
  
  Fig 1: Connecting Hand-Held Tester To DLC3
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Turn the ignition switch on (IG).
5. Turn the tester ON.
6. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / CHECK MODE.
7. Switch the ECM from normal mode to check mode.
8. Make sure the MIL flashes as shown in the illustration.
9. Start the engine.
10. Make sure the MIL goes off.
11. Simulate the conditions of the malfunction described by the customer.
12. Check DTCs and freeze frame data using the tester.
  
  Fig 2: Identifying Blinking Pattern
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Check Mode Procedure

Use the Manual With the Right Hardware

When to See a Mechanic