How Weather (Rain, Dust) Affects VEP RFID Tag Scanning

You've done everything by the book. Your VEP is active, your eWallet is full, and your tag is installed. Yet, on a rainy day, you approach the gantry and... nothing. The scan fails. It's a confusing and frustrating experience that many drivers face.

Heavy rain is the most common weather-related cause of scan failures. It's not about the tag getting 'wet', as it's safely inside your car. The problem occurs on the outside of your windscreen.

• Signal Absorption: Radio waves are absorbed by water. A heavy, continuous sheet of water flowing over your windscreen during a downpour can absorb a significant portion of the RFID signal, weakening it before it reaches the overhead reader.
• Signal Distortion: The chaotic, uneven surface of the water, combined with the sweeping motion of your wipers, can scatter the radio waves. This makes it difficult for the reader to get a clean, uninterrupted signal from your tag.

A less obvious but equally problematic issue is a dirty windscreen.

• Signal Obstruction: A thick layer of dust, mud, or grime on your windscreen acts as a physical barrier. While you might be able to see through it, it can be enough to obstruct the low-power radio waves from your RFID tag, preventing a successful scan.

You can't control the weather, but you can control your preparation.

• Start with a Strong Signal: The best defence is a perfectly placed tag. Professional installation by MyMechanic ensures your tag is in the optimal spot for the strongest possible signal, powerful enough to overcome most weather-related interference.
• Keep it Clean: Regularly clean the inside and outside of your windscreen, paying special attention to the area around the tag.
• Slow Down in Bad Weather: When approaching the gantry in heavy rain, reduce your speed to below 20 km/h. This gives the scanner more time to lock onto a potentially weaker signal.

If you're experiencing consistent scan failures during bad weather, it's a tell-tale sign that your tag's placement is not optimal. Don't leave it to chance.

Frequently Asked Questions