# My car's" Check Engine" light: Has the sensor gone haywire? **URL:** \ **Category:** Factual Questions\ **Created:** [September 1, 2014, 7:43pm UTC](https://boards.straightdope.com/t/my-cars-check-engine-light-has-the-sensor-gone-haywire/697183 "2014-09-01T19:43:02Z")\ **Posts on this page:** 1\ **Showing post:** 15
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [September 2, 2014, 3:40am UTC](https://boards.straightdope.com/t/my-cars-check-engine-light-has-the-sensor-gone-haywire/697183/15 "2014-09-02T03:40:35Z")
Actually **Gary T** hit the nail squarely on the head with this post: > [@Does California law prohibit the sale & rental of auto trouble-code readers](https://boards.straightdope.com/t/does-california-law-prohibit-the-sale-rental-of-auto-trouble-code-readers/678237/24): > > Auto repair facilities in California have to be licensed as such. Performing auto repair service – which can include testing, evaluation, and advice – as a business without said license is a good way to get your tit in a wringer. California’s BAR (Bureau of Automotive Repair) tends to be tough on shops to the point of being overzealous in protecting customers’ interests. It wouldn’t surprise me if parts stores got stung with hefty fines from BAR due to disgruntled customers and decided it wasn’t worth the hassle. Auto Zone is not licensed as an Auto Repair Dealer. Per the BAR reading codes and offering advice falls under auto repair. The BAR has some serious penalties for operating an unlicensed repair shop. In addition even if a parts store were to get licensed there are a whole raft of additional rules that they would have to conform to to read codes. Bottom line it’s easier just to not offer that service. --- _[View the full topic](https://boards.straightdope.com/t/my-cars-check-engine-light-has-the-sensor-gone-haywire/697183)._