Some Malaysian motorists who use electronic tags (eg Smartag and Fastrak) for speedier passage through toll plazas may have encountered problems with the unit’s operation when they have put certain types of tinting film on their windscreen. The problems arise because the systems at the toll plaza use infra-red (IR) beams to communicate with the electronic tag and record payment.
However, because IR brings heat into the cabin, some tinting films are designed to completely prevent IR rays from passing through as a way to keep the cabin cooler. Thus the electronic tag cannot be read and the system doesn’t register payment.
Recognising that IR is a heat source, some manufacturers have also fitted windscreen glass which can reduce IR transmission. There are various ways of making the glass do this and Citroen’s method is to put metal oxide particles in the glass during manufacture.
In France, use of electronic tags that operate with IR rays (using radio waves is not allowed) is quite common so French manufacturers have also come up with solutions to ensure that the tags can be read. Citroen’s solution has been quite simple – to provide a section of clear glass on the area behind the rearview mirror. This allows the IR rays to pass through uninterrupted and reach the tag.
For Singaporean owners of the Citroen C5, which has the special windscreen glass, problems have arisen concerning the electronic tag that must be used for the city’s Electronic Road Pricing (ERP) system. It is not that there are problems for the tag to be read – if it is placed in the area behind the mirror, it can interface with the ERP scanner on the gantry.
The problem is that the Land Transport Authority (LTA) which makes the ERP regulations has stipulated that the electronic tag (known as an In-vehicle Unit or ‘IU’) must be put in a location on top of the middle part of the dashboard, against the glass. Placing it anywhere else is considered an offence (unlike Malaysia where you can even hold the tag outside the window!)
It is not known if any C5 owners have been penalised for the offence but the matter has been serious enough for Advance Automobile, the Citroen importer, to appeal to the LTA to permit C5 owners to put the IU behind the mirror.
According to a statement by the company, when the IU has been placed in the position provided, there has not been any problem in it being read at ERP entry points.
The company is not keen on adopting the solution of changing the special glass to plain glass. “A move to replace a state-of-the-art windscreen with ordinary glass solely because the ERP unit is not in the usual spot, and not for reasons of safety or the malfunctioning of the gadget would be to deprive our C5 customers of one of the latest advances in motoring technology and safety,” said Advance Automobile.
According to a senior executive (which declined to have his name mentioned) in a Singapore car company, the LTA’s rules are usually due to safety reasons. He said that the strict placement of the IU has been questioned before and believes that the reason for the LTA’s chosen position is due to its lower risk of being ‘launched’ during an accident and hitting an occupant. If it is attached to the upper portion of the windscreen, it could drop down and hurt someone.
The executive said that he did not expect the LTA to agree to the appeal by the Citroen importer. “They are typically firm on their regulations and it is not a good idea to challenge them,” he told AUTOWORLD.COM.MY.
It is known that some years ago, Audi had similar problems with its A8 flagship, which has a special type of heat-cutting glass and decided to change the glass on Singapore models to a less high-tech type. BMW also has such glass as an option but does not specify it for cars imported into the republic.