GM charger displays E08; vehicle may show ‘Grounding Issue’ or similar message and refuse to charge.

Safety first: Turn OFF the charger breaker. Grounding issues can create shock hazards.

Homeowner actions:

• Do not use extension cords or adapters with the GM charger.
• Note any recent electrical work or panel upgrades and inform your electrician.

Electrician actions (qualified personnel only):

• Verify continuity and low impedance from the charger ground terminal to the main service ground.
• Inspect and tighten the ground lug inside the charger and at the panel per GM torque specifications.
• Confirm that the charger is fed from a properly bonded panel and that neutrals and grounds are correctly separated in subpanels.

Once the ground path is corrected, clear the error by power cycling the charger. If E08 persists with a verified good ground, the internal ground‑sensing circuit on the GM control board may be defective and the charger should be replaced.