A vehicle onboard diagnostic system (OBD) telematics link now is offered by a California company so that motorists can learn what is wrong with their vehicle before scheduling a repair shop visit.

That system, made by San Diego’s Networkcar, now will compete with Mechanic Net Group, Fremont, CA, which has developed the software to support a similar system.

MechanicNet tells Ward’s that an onboard telematics unit, linked to the OBD system, costs between $500 and $1,000 and that the companies retailing the service charge $10 to $20 per month.

The system employs wireless communication of whatever codes a vehicle’s OBD system generates and then relays the meaning of the code back to the motorist, who can then schedule a shop visit.

The claimed advantage is that both the motorist and the shop know the nature of the fault in advance. The irony, however, is that all 1996 and newer vehicle computers detect and know the fault, but by agreement with the U.S. Environmental Protection Agency, motorists are effectively prevented from direct reading of this information.

Given that situation, motorists currently have two options: One is to visit a repair shop, having no idea what is wrong, and pay a diagnostic fee to learn the nature of the problem. A repair estimate then is offered.

The second option is to have a telematics system installed (described above) and pay the additional monthly fee in order to learn what the diagnostic computer already knows – then visit a repair shop armed with this information.

Ward’s understands that in most cases a diagnostic fee still will be charged, based on the argument that OBD codes are not specific enough in many cases to pinpoint the exact fault (bad electrical connections versus a faulty component, for instance).

Another advantage can be a link with state emissions testing agencies, thereby eliminating the need to appear at a test station. There is no evidence, however, that this idea has progressed past the discussion stage in any state.