Charging more slowly in cold weather is normal and is the car protecting the battery — that part is not a fault. This code means a limit was actually exceeded, which is different. If it appeared at a rapid charger, note which one: equipment that does not respect what the vehicle asks for is a real cause. Otherwise it points at the temperature measurement the limit was based on.
More current has gone into the traction battery than its limit allows.
The two-by-two is at P0CA4. Current limits exist for a different reason from voltage limits, and the reason is the most useful thing on this page.
Charging a lithium cell means persuading lithium to move into the graphite of its negative electrode. When the cell is cold, that process slows down — and if current is forced in faster than the graphite will accept it, the lithium plates out as metal on the surface instead. That is permanent, it costs capacity, and in the worst case the metal grows into structures that can short the cell internally.
Which explains something owners routinely report as a fault and which is the system working properly: an electric car will not rapid-charge at full speed when it is cold. It warms the pack first, or accepts a much lower rate until it has. A winter charge that takes twice as long is the car refusing to damage its own battery.
So this code means a limit set for good reasons was exceeded — either the charging equipment ignored what it was told, or the temperature the limit was based on was measured wrongly, which is why the temperature sensor family matters here.
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Every winter this arrives as a fault report, and almost every time the car is doing exactly what it should. Charging a lithium cell means persuading lithium into the graphite of th...
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