Early detection of plant diseases is crucial to minimize crop losses and reduce the usage of pesticides. Electronic Nose (E-Nose) detect volatile organic compounds (VOCs) emitted by stressed or diseased plants, and one such device is a pixelated capacitive sensor (PCS). We designed and built a setup to investigate the influence of light (wavelength and intensity) on the sensitivity of a functionalized PCS for VOCs detection. Our test results indicate that UV illumination, particularly at 375 nm, enhances the sensitivity of the PCS, with a 3-fold enhancement compared to dark conditions. The sensor showed fast saturation (<1 min) and recovery (<2 min) times, confirming the effectiveness of the chamber design for repeatable gas exposure.