Code RCM_d077 was reported by the “Airbags and restraints” controller in the car. The letter “d” in the middle places it among entries of the diagnostic entry type.
The Restraints Control Module — the controller for airbags, seatbelt pretensioners and crash detection. Codes in this group should never be ignored: they can mean an airbag will not deploy in a collision.
A service record that is not shown to the driver. Only a technician sees it in diagnostics.
This is how the fault is named inside the car's firmware. For codes without a description it is the most precise clue there is — the name itself says what the event is about.
The text below comes from Tesla's technical documentation. We leave it in the original English so that translation cannot shift its meaning.
Cracked SignalDTCRCM_hwcp2CfgRCM_805456RCM_hwcp2CheckFailRCM_805452RCM_hwcp2CrosCoupRCM_80542BRCM_hwcp2UndefinedRCM_80541DRCM_hwcp2OpenRCM_805413RCM_hwcp2Sht2BatRCM_805412RCM_hwcp2ShortRCM_805411
Copy it exactly, letter and number included. Photographing the screen is safest — codes often differ by a single digit, and mixing them up leads somewhere else entirely.
Some codes clear after a screen restart or after the car sits locked for a few hours. If the code does not come back, it was usually a one-off glitch.
A one-off entry and a code that appears after every drive are two different things. It helps a service centre enormously if you know exactly when it shows up.
With airbags, brakes, steering and high voltage there is no point waiting it out. With the other groups you can watch and see whether the code returns at all.
Error codes are only part of the picture. For cars on TesList you also see battery health pulled straight from the vehicle, plus a price calculator that works out from current listings what a given car is actually worth today.