• 1 beep + 2 beeps When your E toll account balance is under the nominated top-up amount, you will hear one beep followed by another two beeps as you drive through the toll plaza. • 4 beeps If your E toll account balance is in debit, your transponder will emit four beeps. E toll is monitored by video surveillance, so a photo will be taken of your vehicle and you will be sent a notice of demand requesting post-payment of the toll fee. An administration fee may also be charged. You may like to consider using the automatic top-up facility, accessible online or through our Call Centre or by visiting one of our Customer Service Centres.