Red high-voltage warning on an EV: stop and call

Critical warning

Stop as safely as you can, get out of the car, and call for help. Do not open the hood and do not try to diagnose it yourself: the system carries lethal voltage.

Can you keep driving?

No. Stop and have the car recovered.

Orange high-voltage cables and a component with a high-voltage warning mark in an electric car

What the warning actually means

The symbol is usually a car or a battery with a lightning bolt in it. It warns about a fault in the high-voltage system, meaning the traction battery and the circuit around it.

Opened electric car traction battery pack with cell modules, coolant channels and high-voltage connections
The traction battery and the circuit around it make up the high-voltage system.

Common causes

  • A fault in the traction battery or its management
  • An insulation fault
  • A fault detected after impact or water damage

What to do now

  1. Stop somewhere safe and switch the car off.
  2. Get out, and keep your distance if you smell anything or see smoke.
  3. Call roadside assistance and say it is a high-voltage warning on an EV.
Red warning triangle set out on the road behind a stopped car
Stop somewhere safe, get out and keep your distance while you call for help.

What people often get wrong

That it can be diagnosed like an ordinary engine fault. The high-voltage system carries lethal voltage, and there is nothing under the hood an owner should touch.

When the car must go to a workshop

Always. This should go to a franchised dealer or a workshop with high-voltage qualifications.

Technician inspecting the underside of an electric car battery on a lift in a workshop
High-voltage faults belong with a workshop that has the right qualifications.

Read next

This page is general information and does not replace a professional assessment. Symbols, codes and behaviour vary between makes. Always check the handbook for your own car.

Was this page helpful?

Tell us what to make next

Is there a warning light, a fault or a repair you want explained? Tell us and we will look at it.

Topic
We only use your email to reply to you.

Know Your Car. Save on Repairs.

Practical guides that help drivers diagnose problems, avoid costly repairs, and maintain their vehicles with confidence.

Our pickDashboard Warning Lights Made Simple

Get the guide that fits this exact problem, with the full explanation in one PDF.

$16.00 See the guide →
FreeDownload free practical guides

Short checklists you can print and keep in the car, ready in seconds.

Get them free →
Browse all guides