Immobiliser or security indicator
A flashing parked security LED is often normal; unexpected rapid flashing, a key symbol or failure to start needs the handbook's key procedure.
Last reviewed: 23 July 2026 · Exact behaviour varies by make, model and year
Normal behaviour
Many motorcycles flash a security LED while parked to show that the immobiliser or alarm is armed. Some stop flashing after a set period to conserve battery power.
Possible fault
Unexpected rapid flashing, a key symbol or failure to start can indicate that the coded key is not recognised, the fob battery is weak or the security system has a fault.
What to do
Follow the handbook's recognition, emergency-start or spare-key procedure. Try the approved spare key if available and replace the fob battery only as directed. Keep other coded keys or interfering objects away if the handbook recommends it.
Possible causes
- •Normal armed-system indication
- •Weak fob battery
- •Damaged or unrecognised key
- •Antenna, wiring or immobiliser fault
- •Aftermarket alarm problem
- •Low motorcycle battery voltage
When not to ride
Do not bypass or remove the security system. If the motorcycle starts but reports a security-system fault, check the handbook before travelling because it may not restart.
Sources
- The Highway Code, warning displays and vehicle maintenancehttps://www.gov.uk/guidance/the-highway-code/annex-6-vehicle-maintenance-safety-and-security
- Honda motorcycle owner's manualshttps://www.honda.co.uk/motorcycles/my-bike/honda-motorcycles-owners-manuals/
- Yamaha motorcycle owner's manualshttps://www.yamaha-motor.eu/gb/en/service-support/owner-manuals/