A gear symbol or a thermometer-in-gear light warns of an automatic gearbox fault or overheating. What to do and limp mode explained.
Looking for more detail? Our full guide covers this topic in depth, with step-by-step advice and sources.
The automatic gearbox or transmission has a fault or is overheating. The car may enter 'limp mode', holding one gear to protect itself.
What it looks like
A cog wheel, sometimes with an exclamation mark or thermometer. Colour: Amber or red.
Common causes
- Overheating in heavy traffic or when towing
- Low transmission fluid
- Sensor or solenoid fault
- Clutch wear in automated manual or dual-clutch gearboxes
What to do
- If it shows overheating, stop safely and let it cool with the engine idling in park, if the handbook advises.
- Avoid aggressive acceleration and heavy loads.
- Have the fault code read; transmission repairs are cheaper if caught early.
Can I keep driving?
Gently, to a safe place or garage, if the car still drives.
MOT
Not a specific MOT item.
Symbols vary slightly between makes. Always check your owner's handbook. General guidance only; if in doubt, call your breakdown provider.
Sources and further reading
Facts checked on 20 October 2026. Spotted an error? Tell us and we will correct it.