HINT:

Compared to the normal mode, check mode is more sensitive to malfunctions. Therefore, check mode can detect the malfunctions that cannot be detected in 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 to ON (ACC) or off while in check mode. Before changing modes, always check and note any DTCs and freeze frame data.

CHECK MODE PROCEDURE (Using Techstream)
1. Check and ensure the following conditions:
  1. Battery positive voltage 11 V or more.
  2. Throttle valve fully closed.
  3. Transmission in the P or N position.
  4. A/C switch OFF.
2. Turn the ignition switch off.
3. Connect Techstream to the DLC3.
4. Turn the ignition switch to ON.
5. Turn the tester on.
6. Enter the following menus: Powertrain/Engine/Utility/Check Mode.
7. Switch the ECM from normal mode to check mode.
8. Make sure that the MIL flashes as shown in the illustration.
9. Start the engine.
10. Make sure that the MIL turns OFF.
11. Simulate the conditions of the malfunction described by the customer.
12. Check for DTCs and freeze frame data using the tester.
  
  Fig 1: MIL Flashes 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