DTC B15CC: Backup Battery Failure [06/2018 - 10/2019]: Procedure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus ES 300h, 2023 Lexus ES 300h, 2022 Lexus ES 300h, 2021 Lexus ES 300h, and 2020 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.

CHECK DTC

Turn the power switch off.
Connect the Techstream to the DLC3.
Turn the power switch on (IG) and wait for 10 seconds.
Turn the Techstream on.
Clear the DTCs.
Body Electrical > Telematics > Clear DTCs

Recheck for DTCs.

Body Electrical > Telematics > Trouble Codes

Result

Result	Proceed to
DTC B15CC is output	A
DTC B15CC is not output	B

Result:

CHECK FOR INTERMITTENT PROBLEMS. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [06/2018 - ]

Result:

See step 2

REPLACE BUB (BACK-UP BATTERY)

Replace the BUB (Back-Up Battery) with a new one and check if the same problem occurs again.

Refer to REMOVAL [06/2018 - 10/2019]

NOTE:

The BUB (Back-Up Battery) must not be replaced while an ACN call is in progress.

Refer to ACN CALL END [06/2018 - 10/2019]

Result

Proceed to
NEXT

Result:

See step 3

CLEAR DTC

Clear the DTCs.

Refer to DTC CHECK / CLEAR [06/2018 - 10/2019]

Result

Proceed to
NEXT

Result:

See step 4

RECHECK DTC

Recheck for DTCs and check if the same trouble occurs again.

Refer to DTC CHECK / CLEAR [06/2018 - 10/2019]

No DTC is output.

Result

Proceed to
OK
NG

Result:

END

Result:

See step 5

REPLACE DCM (TELEMATICS TRANSCEIVER)

Replace the DCM (Telematics Transceiver).

Refer to REMOVAL [06/2018 - 10/2019]

NOTE:

The power switch must be off.
Do not swap the DCM (Telematics Transceiver) with one from another vehicle.

Result

Proceed to
NEXT

Result:

PERFORM DCM ACTIVATION. Refer to DCM ACTIVATION [06/2018 - 10/2019]