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RecallGazette

Vehicle problems, recalls & safety intelligence

Toyota 4RUNNER 2017–2021technical service bulletin

Bulletin T-TT-0516-18_Rev · NHTSA communication 10176493 · issued May 13, 2020

Technical service bulletin
communication type
Equipment
component
2017–2021
model years
34
vehicle entries

Official summary

TT: The microphone circuit passes through the DCM before reaching the radio/navigation system. To simplify the diagnosis of the microphone, Safety Connect SOS button lights, and DCM (Data Communication Module/telematics transceiver) inoperative conditions, refer to the procedure below to prevent unnecessary parts replacement.

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.