Monday, January 23, 2012

Ban the 'check engine' light.

We all know the 'check engine' light. For car enthusiasts it's a slap in the face. For people who just view their vehicle as A-to-B transport, it's dangerous. It obscures all manner of problems, shrouding them in a fog of mystery and making it easier for dishonest mechanics to take advantage of unknowing customers. We have chimes and lights on the dash for seatbelts, lights, low tyre pressures and keys left in the ignition but that check engine light can be anything from a loose petrol cap to an engine on the verge of destroying itself. All modern cars are equipped with OBD-II onboard diagnostics - they have been since 1996. We have the ability to put LCD displays in just about everything now so why not replace the check engine light with an LCD display that tells the owner what's actually wrong? Instead we have to rely on nerds like me with handheld scanners and an internet connection, products like the excellent CarMD or sometimes less-than-scrupulous dealers and mechanics with their "special tool".
In the US at least, there are federal mandates for things like tyre pressure warning systems and airbag warning lights - isn't it about time we got them to ban the check engine light and force manufacturers to put something more useful in its place? It can't be a cost issue - look at all the funky new electronic gizmos that are being put in cars now from pointless touchscreen interfaces to even more pointless auto-lights. Is it perhaps some conspiracy theory to keep dealers and mechanics profitable by hiding what could be a very simple problem from largely ignorant owners?
If, like me, you think the check engine light has had its day and you think there's a better opportunity, then go and sign the petition: Ban the check engine light.
In the meantime I can make life a little easier for you as I have a CarMD to give away in a competition. Head on over and try your luck. At the very least you'll be able to go to the mechanic with some level of knowledge next time that little yellow light comes on.


Paul said...

This is a good call Chris. I have to admit I haven't really thought about it before as I use an OBDII analyzer to check what the problem might be.
I've signed the petition.

Anonymous said...

The CEL is there because 90% of the population doesn't know what OBDII is, let alone enough to connect a scan tool to their cars. The general public does not want to repair their own vehicles - they just want to take them to a mechanic who will fix everything. The CEL provides the minimum amount of info for the consumer to know that there is a problem that is impacting their vehicle's emissions, and that it needs to be fixed. As you mentioned in the article, the other system-specific lights are only there because of federal mandate.

It may seem overly-simplified, but I don't think anyone is going to be dissuaded from working on there own car just because they don't have a scan tool, especially since so many auto parts stores rent them for free or a small fee. The ones who take their cars to a mechanic are the ones who wouldn't know what to do with a PXXXX code if it bit them in the face.

Chris said...

The CEL isn't just for emissions. And therein lies the problem. People don't really know what it's for. Some ignore it. Some are afraid of it. It can report error codes from something as simple as loose gas cap to something altogether more worrying like timing issues. Emissions are only part of the equation.

Anonymous said...

Unfortunately, Chris, that's not quite accurate. The OBDII legislation dictates that the CEL is only to come on when the vehicle has a problem that will adversely affect its emissions - steady if the problem is not immediately damaging to the catalytic converter, and flashing if it is (such a misfire). The ECU can still log trouble codes for other vehicular systems (e.g., transmission, auxiliary systems, etc.), but it will not turn on the CEL.

That's why, even if your CEL isn't on, I still recommend connecting a scan tool to your car once every couple of months to see if there are any trouble codes. You mentioned the gas cap in particular - this would turn on the CEL, because a loose gas cap will allow fuel vapors (i.e., evaporative emissions) to escape into the atmosphere, as opposed to being properly routed to the vehicle's charcoal canister and burned in the engine.


Anonymous said...

Now there is another light on some vehicles, the "Service Engine Soon" light. This light is the true enigma, because it can indicate anything from a simple odometer reading that has been reached (e.g., you reach the 30k mile mark, and the carmaker assumes that you need to be reminded about your 30k mile maintenance), to a major problem with the vehicle. Honda is particularly notorious with this light, because on many of their cars you need their proprietary scan tool ($5k and up) to find out why the light is on.

Unfortunately, and I'm not suggesting that this is the case here, but I've seen many folks come in and tell me that their Check Engine Light is on, when in fact it is their Service Engine Soon light. There are some basic checks that you can make to rule out any obvious reasons for the light, but ultimately we end up sending them down the road to the Honda dealer to get the light cleared (and thus limit our liability).