The Automotive EMC Directive

The principal challenge is for the UK's automotive manufacturing industry to align its technology, product and business performance to deliver customer value in a global industry subject to relentless cost-cutting pressures.

This poses further regulation challenges; The Automotive EMC Directive is a regulation that requires manufacturers to gain type approval for all vehicles and electronic sub assemblies (ESA's), components and separate technical units (STU's) to be used in vehicles. Certain types of equipment are exempt from certain tests. Equipment for caravans and motor homes that operate when the vehicle is in use are included in the Directive, but those that only operate when the vehicle is parked or are powered independently are excluded.

Manufacturers and suppliers to the automotive industry need to demonstrate that their product (whether it is a whole vehicle, separate technical unit or electronic sub assembly) is fit for purpose and is safe. This means in the context of the Automotive EMC Directive (2004/104/EC) that

  1. The electrical noise from the product is kept within defined limits, that protect other electrical equipment and radio broadcast services and;
  2. Is immune to the electrical noise produced by the vehicle and other electrical equipment used in close proximity to the product.

The introduction of the current Automotive EMC Directive (2004/104/EC as amended by 2006/28/EC & 2009/19/EC) provides greater flexibility for the manufacturer where the product does not have an 'immunity related function'. It allows such equipment to not be 'type approved' (e-marked) but have only limited tests applied instead - simply requiring the radiated emissions it produces and immunity to conducted transients to be checked instead of all of the tests. Figure 1 provides guidance on the applicability of the automotive directive and the overlap with other related directives.

It is argued that if a product does not have an immunity related function and stops working as intended in its normal environment, it will not comprise the safety of the vehicle. Any malfunction would then been seen as a quality issue and would be self-policed by the market.

So what is an 'immunity related function'?

Immunity-related functions are:

Functions related to the direct control of the vehicle:

  • by degradation or change in engine, gear, brake, suspension, active steering, speed limitation devices, for example;
  • by affecting driver’s position, e.g. seat or steering wheel positioning;
  • by affecting driver’s visibility: e.g. dipped beam, windscreen wiper.

Functions related to driver, passenger and other road-user protection:

  • e.g. airbag and safety restraint systems.

Functions which, when disturbed, cause confusion to the driver or other road users:

  • optical disturbances: incorrect operation of e.g. direction indicators, stop lamps, end outline marker lamps, rear position lamp, light bars for emergency system, wrong information from warning indicators, lamps or displays related to functions in clauses (a) or (b) which might be observed in the direct view of the driver;
  • acoustical disturbances: incorrect operation of anti-theft alarm, horn, for example.

Functions related to vehicle data bus functionality:

  • by blocking data transmission on vehicle data bus-systems, which are used to transmit data, required to ensure the correct functioning of other immunity-related functions.

Functions which, when disturbed, affect vehicle statutory data:

  • e.g. tachograph, odometer.

Products that can be used in dual environments (non-automotive commercial and automotive use) will require assessment to both sets of regulations and may be required to carry both an e-mark and CE mark. This is certainly the case where radio products are concerned. This is because a radio product is covered by a specific directive covering all radio and telecom terminal equipment (R&TTE Directive, 1999/5/EC).  The diagram below provides a decision tree of when to apply CE marking versus e-marking.

EMC Automotive Directive

It would appear that little is known about the change to the directive’s requirements, which potentially has a major impact on the design of the product since the test requirements are now different.  Directive 2004/104/EC replaces the old directive, 95/54/EC (which was based on 72/245/EC). Manufacturers of aftermarket products had until the end of 2008 to upgrade to 2004/104/EC, any previous type approval certificate expired at the end of 2008.

It should be noted that the overarching framework directive 2007/46/EC which references 2004/104/EC was extended on 29 April 2009 to cover all new road vehicles and trailers. The implementation period for trailers and second stage builds is longer (i.e. where an approved vehicle is procured and modified) and this will not become mandatory until 2012.