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THEFT DETERRENT / KEYLESS ENTRY SMART ENTRY AND START SYSTEM(for Start Function) B2277 Detecting
Vehicle Submersion

DESCRIPTION

This DTC is stored when a malfunction in the water submersion detection circuit in the certification ECU (smart key ECU
assembly) is detected.
HINT:
When the cable is disconnected and reconnected to the negative (-) battery terminal, the power source mode returns to the
state it was in before the cable was disconnected.

DTC Detection
DTC No. Detection Item Trouble Area Note
Condition

· Submersion of
The water submersion certification
detection circuit in the ECU (smart key Wait 300 seconds
certification ECU (smart ECU assembly)
Detecting Vehicle after connecting the
B2277 key ECU assembly) in water
Submersion cable to the negative
detects water · Certification (-) battery terminal.
submersion (1-trip ECU (smart key
detection logic*). ECU assembly)

*: Only detected while a malfunction is present.

Vehicle Condition and Fail-safe Function when Malfunction Detected

Vehicle Condition when Malfunction Detected Fail-safe Function when Malfunction Detected
The engine switch cannot be turned off and the engine
-
cannot be started.

Related Data List and Active Test Items

DTC No. Data List Item Active Test Item
B2277 - -

CAUTION / NOTICE / HINT

NOTICE:
· When using the GTS with the engine switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off
at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select the Model
Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). While
using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain
communication between the GTS and the vehicle.
· The smart entry and start system (for Start Function) uses a multiplex communication system (LIN communication
system) and the CAN communication system. Inspect the communication function by following How to Proceed with
Troubleshooting (Click hereVehicle Interior>THEFT DETERRENT / KEYLESS ENTRY>SMART ENTRY AND START SYSTEM
(for Start Function)>HOW TO PROCEED WITH TROUBLESHOOTING). Troubleshoot the smart entry and start system (for
Start Function) after confirming that the communication systems are functioning properly.
· Before replacing the certification ECU (smart key ECU assembly), refer to the smart entry and start system (for Entry
Function) precaution.
Click hereVehicle Interior>THEFT DETERRENT / KEYLESS ENTRY>SMART ENTRY AND START SYSTEM (for Entry
Function)>PRECAUTION
· After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm
that no DTCs are output again.

HINT:
Before proceeding with troubleshooting, check if there are any signs of water damage to the certification ECU (smart key ECU
assembly). If there are any signs of water damage, replace the certification ECU (smart key ECU assembly) and take measures
against the cause of the water damage.

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16:15, 02/02/2023 Print-Toyota Service Information

PROCEDURE

1.CHECK WATER INTRUSION

a. Check that the certification ECU (smart key ECU assembly), its surrounding area and harnesses have no signs of water
intrusion.

Result:
Result Proceed to
No sign of water intrusion found A
Signs of water intrusion found B

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

TAKE MEASURES FOR WATER INTRUSION AND REPLACE CERTIFICATION ECU (SMART KEY ECU
ASSEMBLY)

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