How to turn the lights on and off on a Mahle X35 / X20 bike
On bikes with lights wired to the Mahle system, a long press of the iWoc toggles them. The app can set Auto on the X20.
Step by step
- With the bike on, press and hold the iWoc button for about 2 seconds. Lights come on; the LED blinks once.
- Hold again to switch off.
- X20 with app: Settings > 'Lights' > Auto / On / Off.
- Lights switch off when the bike goes to sleep.
Tip: If holding the iWoc switches the bike off instead, hold for exactly 2 seconds, not longer; 5 seconds is power-off.
Can't find it?
No reaction at all: your bike's lights are not wired to the Mahle system (some road bikes run separate USB lights).
Frequently asked
Lights on but no assist?
Battery below 5%; the system keeps lights on and drops assist first.
Can I add lights to an X35 road bike?
Yes; the rear-light port on the battery/controller gives 6V. A dealer enables it in the service tool.
Do lights cost range?
About 2%.
Manuals and video
Videos found on YouTube and checked automatically; they are other people's work, not ours.
- Ribble e-bike purple flashing light fault - MAHLE X35 motor Solo Biker Dave
- Lightweight e-Bike Mahle X35+ System Review Beyond the Bike Roads
Other Mahle X35 / X20 (iWoc button, My SmartBike app) guides
Mahle: connect the My SmartBike appMahle: firmware updateMahle: assist levels and customisationMahle: switch mph to km/hMahle: walk assistMahle: speed limit
Still stuck? Take a photo of the display and show it to a local e-bike workshop. Bring the bike's system name (e.g. Bosch Performance Line CX) and the exact code; that saves diagnostic time and money.