Yamaha FI Code 19: Sidestand Switch — Fix
On Yamaha motorcycles and scooters, FI fault code 19 means an open circuit was detected in the input lead from the sidestand switch to the ECU — the switch that cuts the engine if you ride off with the stand down.
- Applies to
- Yamaha motorcycles
- Est. repair cost
- $15 – $90
- Time to fix
- 30–90 minutes
What it means
Common causes are a loose/corroded sidestand-switch connector, damaged wiring near the stand, or a failed switch. This is a generic Yamaha fuel-injection (FI) fault code, so it applies across Yamaha FI models — scooters and underbones like the Mio, NMAX, Aerox, and Sniper, plus YZF-R and MT motorcycles. Yamaha shows the code as a number on the diagnostic/odometer display, and the engine-warning light comes on. Once the fault is repaired and the ECU no longer detects it, the code clears; cycling the ignition (or using a Yamaha diagnostic tool) may be needed to confirm.
Symptoms
- FI code 19 with warning light on
- Engine cuts out or won’t start, especially in gear
- Sidestand warning behaviour
How to fix it
- 1
Inspect the sidestand switch and wiring
1. Locate the switch at the sidestand pivot. 2. Reseat the connector and check the wiring for damage from movement.
- 2
Test and replace
1. Confirm the switch changes state as the stand is raised/lowered. 2. Replace if faulty, then clear the code.
Frequently asked questions
Why does my bike cut out in gear with code 19?
The sidestand switch is part of the safety cut-off. A fault in its circuit can trigger the cut-out or block starting in gear. Check the switch and its wiring.
Last updated July 16, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.