Check Engine Light: How much is software and how much are components?

You’re driving to work, trying to avoid total obliteration at the hands of a speed-crazed long-haul trucker, listening to your favorite talk show person filling your damaged psyche with the trollish behavior of assorted witless politicians; you’re having a reasonably normal morning commute. Ho, hum!

You see an orange light flashing on the instrument panel. The manufacturer has cleverly created the light in the shape of an automobile engine. This is useful if you are newly arrived from Waziristan or a graduate of the Los Angeles Unified School District.

Decision time: Should you pull over and stop? Should you try to continue and drive to your dealer? Getting a tow truck is going to be a serious pain in the…back. The engine coughs and stumbles like a wounded duck. No choice now, it’s off to the dealership.

If this has happened to you, you know what comes next. “It’s diagnosis time.” Cue the sad, mysterious music. At the dealership, the technician hooks a device to your vehicle’s computer network that reads the contents of one or more of the computers that control all of the operations of your engine.

I will spare you the descriptions of some of the truly idiotic diagnoses, such as, “you didn’t tighten the gas cap properly,” Such shenanigans may appear in another post. What happens is the technician asserts that the #2 ignition coil has failed. “How do you know that?” you ask. “Oh, well, my test device read the DTC (Dynamic Trouble Code) 2P4356. It was stored in the computer. We’ll replace the coil; everything will run fine.”

As your eyes glaze over in dumb admiration for this display of modern technology, you feel comforted to know that all that ‘stuff’ shoe-horned into the space beneath the hood isn’t so mysterious at all.

If, however, you know engine components and control systems, and you know software systems, your reaction might be a bit different. You say, “If there are approximately 500 to 1,500 components in that engine, and maybe 250,000 lines of software code controlling all aspects of the engine, maybe it’s the software!”

This really is the question, isn’t it? Without being a software expert, logic suggests that there is certainly as much chance that there was a problem in the software code as there is of the ignition coil being defective. If you look at the numbers, they suggest that there’s an even greater chance that something is wrong with the software.

After having reviewed over 8,000 California Lemon Law cases, experience bears out our assertions. One might wonder with these facts in mind, why do the dealerships keep throwing parts at the problem and ignore the software.

The next time you are tooling down the highway and your check engine light starts flashing, remember that there’s a greater chance that something is wrong with the software than the hardware. Here’s the cheerful news: It’s easier to re-write code than it is to re-design a badly designed part. Here’s the not so cheerful news. It’s more expensive to re-write software than it is to re-design hardware. Sorry!

There ought to be enough ideas here to get some agreement and some disagreement. We would certainly like to hear both.