Suzuki FI Code C14: Throttle Position Sensor — Causes & Fix
On Suzuki motorcycles and scooters, FI code C14 means a fault in the throttle position sensor (TPS) circuit — the sensor that tells the ECM how far the throttle is open.
- Applies to
- Suzuki motorcycles
- Est. repair cost
- $20 – $140
- Time to fix
- 30–90 minutes
What it means
Usual causes are a loose/corroded TPS connector, a worn or misadjusted sensor, or damaged wiring. This is a generic Suzuki fuel-injection (FI) code, so it applies across Suzuki FI models — the Raider R150 Fi, Smash, Gixxer, GSX-R and GSX-S range, V-Strom, and more. Suzuki reports it as a "C" number, shown through the FI-light blink pattern or by entering the bike’s dealer/diagnostic mode. After the fault is repaired it becomes a stored "history" code; clear it through Suzuki’s dealer/diagnostic mode so the FI light goes out.
Symptoms
- FI light on with code C14
- Jerky throttle, surging, or flat spots
- Stalling on deceleration
How to fix it
- 1
Inspect and reseat the TPS connector
1. Locate the TPS on the throttle body. 2. Reseat the connector and check the harness for chafing.
- 2
Check the voltage sweep, then adjust/replace
1. Backprobe the signal wire and open the throttle slowly — the voltage should climb smoothly. 2. Set the TPS to spec or replace it, then clear the code.
Frequently asked questions
Why does my Gixxer surge with C14?
A jumpy throttle-position signal makes the ECM keep changing fuel delivery, felt as surging. A worn TPS or poor connection is the usual culprit.
Last updated July 15, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.