General Motors has begun replacing Chevy Volt 120 volt charging cords with ones using thicker wires. The move came following months of Volt owner reports of overheating charging cords.

The process involves replacing the existing 120 volt charger (standard equipment with the Chevy Volt) with a new device. The new charger is reported to have thicker wiring on the 120 volt side, and otherwise it would look the same. GM states that the Chevy Volt owners will shortly receive letters notifying them of the upgrade procedure.

Randal Fox, GM spokesman, quoted as saying it is not officially a recall, but a program under customer satisfaction.

Even in the past, GM insisted the 120 volt charging cords were safe despite the occasional report of hot cords. Electrical engineers predict that thin wire is barely adequate to the task of carrying the 1.5 kilowatts charge rate at 120 volts, especially over the long periods required to recharge a car. The new chargers are reported to have 14 gauge wire and is a “more industrial looking plug and cord.” The thicker wire is consistent with decreasing cord heating due to thin wire.

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