GATINEAU, Que. -- Consumer groups are calling on Canada's telecom regulator to crack down on service providers that aren't living up to the national wireless code of conduct.

The groups, fronted by the Public Interest Advocacy Centre, say some cellphone companies are either passively or actively violating the four-year-old code and consumers are paying more than they should for service as a result.

PIAC executive director John Lawford says the code, to a great extent, has helped protect consumers from so-called bill shock.

But Lawford told the Canadian Radio-television and Telecommunications Commission today the code should be tightened to give wireless users greater control of what they pay for service.

The CRTC is holding a hearing this week to examine whether the code needs to be updated.

The regulator says the hearing will look at a range of issues including ways to give parents more control over household cellphone data charges and whether rules governing wireless service cancellation fees need to be clarified.