B15A8 on Toyota
Telematics Transceiver Malfunction
B15A8 on Toyota vehicles indicates telematics transceiver malfunction. Au7o has documented this code across 2 Toyota models — most commonly on Camry, RAV4. Set by the Data Communication Module (DCM, the telematics transceiver) when its power-on self-check finds an internal error in the EEPROM (which stores the data needed to operate the Safety Connect system) or in the PLL IC (which oscillates the cellular radio frequency). It is an internal-module fault, not a wiring-continuity fault, though a poor connection at the DCM connector can also set it. Toyota has documented that this DTC can be stored during manufacturing and shipping without indicating any real vehicle defect.
Common Causes of B15A8
- •Internal EEPROM or PLL IC failure inside the DCM / telematics transceiver
- •Poor electrical connection or corrosion at the DCM connector
- •DCM firmware fault (including the DCM firmware that keeps the module awake and drains the 12V battery)
- •Code stored during vehicle manufacture or shipping with no actual fault present
B15A8 on Toyota by Model
Toyota Camry(1 issue)
- 2020-2021 DCM-Related 12-Volt Battery Discharge (T-SB-0095-20)2020-2021
Toyota T-SB-0095-20 applies to some 2020-2021 Camry and Camry Hybrid vehicles that may have a depleted 12-volt battery while the ignition is off. The same DCM firmware condition may also present with B15A804 in current or history, a red SOS LED that remains on after bulb check, an inoperative Toyota App, inability to subscribe to remote services, or inability to activate Wi-Fi. This evidence does not support a generic 2018-2023 claim or prove that every discharged Camry battery is caused by the DCM.
Toyota RAV4(1 issue)
- 2020-2021 RAV4 DCM Firmware May Deplete the 12V Battery While Off2020-2021
Toyota T-SB-0095-20 Rev2 applies to some 2020-2021 RAV4 and RAV4 Hybrid vehicles that may exhibit a depleted 12V battery while the ignition is off, sometimes with DTC B15A804, an abnormal SOS indicator or connected-services problems. Toyota's remedy is a DCM reset and firmware update after the bulletin's diagnostic gates. The bulletin excludes RAV4 Prime and does not support the prior 2019-2022 scope, the claim that a hybrid's 12V battery charges only while moving, or a universal battery-replacement diagnosis.
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View B15A8 across all makes →Frequently Asked Questions
What does B15A8 mean on Toyota?▼
B15A8 stands for "Telematics Transceiver Malfunction." Set by the Data Communication Module (DCM, the telematics transceiver) when its power-on self-check finds an internal error in the EEPROM (which stores the data needed to operate the Safety Connect system) or in the PLL IC (which oscillates the cellular radio frequency). It is an internal-module fault, not a wiring-continuity fault, though a poor connection at the DCM connector can also set it. Toyota has documented that this DTC can be stored during manufacturing and shipping without indicating any real vehicle defect. On Toyota specifically, this code is documented across 2 models.
What causes B15A8 on Toyota vehicles?▼
Common causes on Toyota: Internal EEPROM or PLL IC failure inside the DCM / telematics transceiver, Poor electrical connection or corrosion at the DCM connector, DCM firmware fault (including the DCM firmware that keeps the module awake and drains the 12V battery), Code stored during vehicle manufacture or shipping with no actual fault present. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix B15A8 on a Toyota?▼
Repair costs vary widely depending on the root cause and specific Toyota model.
Which Toyota models have B15A8 documented?▼
Au7o has documented B15A8 on 2 Toyota models: Camry, RAV4.