Toyota Avalon Service & Repair Manual: Check Mode Procedure



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


All of the stored DTCs and Freeze Frame Data are cleared if: 1) the ECM is changed from normal mode to check mode or vice versa; or 2) the power switch is turned from on (IG) to on (ACC) or off while in check mode. Before changing modes, always check for and note any DTCs and Freeze Frame Data.


(a) Check and ensure the following conditions:

(1) Auxiliary battery voltage is 11 V or higher.

(2) Accelerator pedal fully released.

(3) Shift lever is in P or N.

(4) A/C switch is off.

(b) Turn the power switch off.

(c) Connect the Techstream to the DLC3.

(d) Turn the power switch on (IG).

(e) Turn the Techstream on.

(f) Enter the following menus: Powertrain / Engine / Utility / Check Mode.

Powertrain > Engine > Utility

Tester Display

Check Mode

(g) Change the ECM from normal mode to check mode.

(h) Check that the MIL flashes as shown in the illustration.

(i) Turn the power switch on (READY).

(j) Check that the MIL turns off.

(k) Simulate the conditions of the malfunction described by the customer.

(l) Check for DTCs and Freeze Frame Data using the Techstream.

    Check For Intermittent Problems

    Checking Monitor Status

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