The answer to 'why is my EV charger dimming lights' is that the EV charger may be drawing too much power, causing a voltage drop that dims the lights. This is a common issue when the electrical system is not properly sized or grounded for the EV charger's power requirements.
Some common causes include an overloaded circuit, inadequate wiring, or a problem with the home's electrical service panel. Symptoms may include flickering, dimming, or buzzing lights when the EV charger is in use. To resolve the issue, you may need to upgrade the electrical service, install a dedicated circuit for the EV charger, or have an electrician troubleshoot and resolve the voltage drop problem.