As vehicle manufacturers rely more on computers to perform various functions in cars, several of the manufacturers fear that giving consumers access to vehicle diagnostic information will leave them exposed, according to Telematics Update.

Toyota's recent troubles are a prime example because one of the recalls resulted from an electronic control unit error that caused a glitch in brake pads.

One telematics company representative noted that when people other than the vehicle manufacturer can data, that data becomes evidence that the manufacturer knew of quality issues prior to recall.

Others in the industry, however, see diagnostic information as a business opportunity. As consumers become more interested in making their cars as connected as their phones and laptops, some OEMs and after-market companies believe vehicle diagnostic information can help drivers analyze their driving performance and understand how to improve it.

A new software supplement called the ecoRoute allows drivers to monitor diagnostic information regarding braking, acceleration, speed, and fuel use on their personal navigation devices. Another product called NDrive keeps drivers abreast of vehicle diagnostic information and conveys that information on the personal navigation device, text message, Web app, or iPhone app.

The emergence of electric vehicles has spurred interest even further. GM has produced smartphone apps for the Chevrolet Volt, which let drivers know about the state of charge, electric and total ranges, and fuel economy performance data for both miles-per-gallon and electric-only miles. And GM's OnStar service runs diagnostic and maintenance checks on subscribers' cars and then delivers reports of those checks by email.

But industry experts caution that vehicle diagnostic information may not boom any time soon. Most consumers haven't been exposed to in-car navigation and in-car infotainment, meaning demand for basic connected services remains slim.