What is this?
EV chargers use LED lights and displays to communicate their status. A red light or error indication means the charger has detected a fault and has stopped or will not start charging as a safety precaution. The specific pattern or code varies by manufacturer.
Common causes
- Earth fault detected by the charger's internal RCD
- Over-temperature — charger has overheated
- Communication error between charger and vehicle
- Supply fault — voltage or frequency out of range
- Internal hardware fault — relay, contactor, or sensor failure
- Charger firmware error requiring a restart or update
Is it dangerous?
The error light means the charger has detected a potentially unsafe condition and has protected you by stopping. This is the charger working as designed. Do not attempt to bypass the error. If the error is an earth fault or over-temperature warning, the charger should be checked before resuming use.
Can I fix it myself?
Note the exact light colour, pattern, and any error codes. Check the manufacturer's app and manual for what the error means. Try restarting the charger by switching the isolator off for 60 seconds and back on. Check the charging cable for damage. If the error is temperature-related, wait for the charger to cool down — direct sunlight on a hot day can cause overheating.
When to call an electrician
Call an electrician if the error persists after restarting, if the error code indicates an earth fault, if the charger shows a hardware error that the manufacturer confirms needs an electrical inspection, or if the error appeared after a power surge or electrical work on the property.
What will an electrician do?
Read and interpret the charger error codes
Test the supply circuit for voltage, frequency, and earth integrity
Check the charger's internal protection devices
Inspect wiring connections for heat damage or looseness
Liaise with the manufacturer for diagnosis and potential warranty replacement
Replace or repair the charger if the fault is confirmed as a hardware issue
Typical cost
£80 – £280
Diagnosis and supply-side repairs are at the lower end. If the charger needs warranty replacement, the electrician may charge for the visit and the disconnection/reconnection. Check warranty coverage before authorising work on the charger itself.
