Symptoms
- Warning message about the EV or drive system appears on the dashboard
- Car accelerates noticeably slower than normal
- Top speed may be limited
- Warning may appear suddenly or build up with other symptoms
Likely causes
- CommonDrive system fault detected by the car's computerThe car intentionally limits power as a protective measure when it detects an issue with the motor, inverter, or battery system.
- PossibleOverheating of a drive componentExtended hard driving, towing, or very hot weather can cause temporary overheating protection to engage.
- PossibleSoftware glitch requiring a restartOccasionally a temporary software issue triggers the warning without an underlying hardware problem.
- PossibleSensor faultA single failed sensor can sometimes cause the system to limit power out of caution even if the actual component is fine.
What to do
- Pull over safely if the warning appears while driving, especially if power is significantly reduced.
- Turn the car off, wait a few minutes, and restart to see if the warning clears, which can happen with temporary software glitches.
- If the warning appeared during hard driving, towing, or extreme heat, let the car cool down before continuing.
- Avoid continuing to drive aggressively or on the highway if power feels significantly limited.
- Note the exact wording of the message and when it appeared, since this helps with diagnosis.
- If the warning persists after a restart and cooldown, have the car towed or driven gently to a dealer rather than continuing normal use.
When to call a pro
A 'service EV system' or reduced power warning should be diagnosed by a dealer or EV-certified shop, since it can range from a minor sensor issue to a significant drive system fault.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.