What is the "Service High Voltage Charging System" Error problem on a 2012 Chevrolet Volt?

Reliability Guide

Common Problems with the
2012 Chevrolet Volt

We've identified 1 known issue that can affect the 2012 Chevrolet Volt. None are considered critical, but they're worth knowing about before you buy.

Known Issues

Serious

Moderate

Minor

ModerateElectrics & Electronics

Usually caused by a low coolant level in the battery cooling loop or a faulty sensor. It prevents the car from charging.

Est. Repair Cost: £100–£400 (Sensor/Flush)

Warning Signs:

Car will not charge, Error message on main display

What to Inspect:

Check the three coolant expansion tanks in the engine bay (one is for the battery)

Verified by IsItAGoodCar Research Team

✓Test drive the car to ensure the transition between battery power and the petrol range-extender generator is smooth and seamless.
✓Check the dashboard for the "Service High Voltage System" message, a known issue often requiring a software update or coolant level sensor fix.
✓Verify the health of the 12V auxiliary battery; a failing 12V battery can cause a cascade of bizarre electrical faults.
✓Ensure the charging cable locks securely into the port and the car accepts a charge without error messages.
✓Check the condition of the low-slung front rubber air dam, which scrapes easily on UK speed bumps.
✓Inspect the service history to confirm that the battery coolant loops have been flushed and replaced according to schedule.