Code SCCM_a018 was reported by the “Steering column stalks” controller in the car. The letter “a” in the middle places it among entries of the alert type.
The steering column control module — indicator, wiper and gear stalks plus the park button. These codes describe shorts and open circuits in the stalks; they show up as being unable to select a gear or a dead indicator.
The most common type. The car logged the event and may have shown it on the screen. The range is wide — from something trivial that clears itself to something that needs attention.
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.
Steering Angle Sensor Speed Threshold Exceeded
Supercharger timed-out during the voltage matching part of the sequence
Voltage matching took too long to occur and the Supercharger timed out
Voltage matching is successful and vehicle closes FC contactors
Vehicle will not close FC contactors and charging will not start up.
Supercharger measuered a low isolation measurement while connected to the vehicle.
Supercharger isolation measurement result was less than the fault threshold
Supercharger isolation measurement result is greater than the fault threshold
Breakdown of isolation on the Supercharger or Vehicle's HV link.
Supercharger did not receive all of the expected messages from the BMS.
All BMS messages where received by the Supercharger.
An emergency shutdown can occur while charging, or charging may never start up.
Could not determine the status of the Proximity connection between the vehicle and the Supercharger
Proximity Voltage is not within any valid range while connected to a Supercharger.
Proximity returns to a valid value.
Supercharger detected a voltage arc, either legitimately, or as a result of the HV circuit being opened under load.
Supercharger detects a rapid change in energy on the HV bus, matching the signiture for an arc
Supercharger has shutdown or been disconnected.
May result in thermal damage to components, or welding/fatigue on FC contactors.
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.