Diagnose Why Your Car's "Check Engine" Light Is On

Diagnose Why Your Car's "Check Engine" Light Is On A Useful Device -- If It Works

by Daniel P. Dern (dern@pair.com)

Vendor: CarMD Corporation Product Name: CarMD Price (MSRP): $89.99 Availability: Now Product URL: www.carmd.com

Tech Requirements: Windows 98 or later for PC software

The "Check Engine" light on car dashboards makes Windows Blue Screen of Death seem chatty and informative -- and most of the diagnostic devices that connect to car computers are pricey and mechanic-oriented.

So CarMD's handheld CarMD seems like a great idea -- a sub-$100 device which plugs in to the On-Board Diagnostics II port in your

1996-or-later car, light truck, SUV or minivan, offers an instant green/yellow/red LED status, and captures diagnostic codes for

uploading to the CarMD web site's database, presenting you with likely diagnosis, and repair estimates based on this. And if you aren't near your computer -- e.g., you're by the side of the road -- you can call the code in to CarMD's 1-800 number from your cell phone. CarMD's database may confirm that $800 estimate -- or suggest something far less expensive.

Also, the color LEDs provide basic-level information. Green means your CheckEngine light and emissions are OK -- and if this is on a car you're considering buying, it's worth continuing thinking about. Yellow or Red mean "think twice and ask about recent service."

Other uses include seeing if your vehicle is ready to pass an emissions "smog" test.

CarMD works on any 1996 or later vehicle (older ones, like my Saturn, have a different interface port). You're allowed to use the web database for up to three vehicles (based on VIN numbers).

I'd love to say this isn't simply a good idea, but also a good tool, but so far, in my testing:

1) The web site has no sample screens showing database/diagnostic results, which would be nice pre-purchase info, instead of just a bunch of testimonials.

2) Connecting it to one car yielded "Error" on the device.

3) ZoneAlarm thinks the software wants to do all sorts of dubious stuff.

4) To run properly, tech support says the software needs MSIE set as your default browser.

5) The device has a power switch, but I don't see any info why, given that you are told NOT to power it on before connecting to a car. (It's for follow-up looking, tech support says.)

I was able to get the handheld, local software, and web site to

all work, talk to each other, and display a diagnostic report... but that took a software download and re-install from the site, and two calls from (a very patient) tech support. The software and web site fail silently without MSIE, JavaScript and cookies.

Of course (ahem), your mileage may vary.

I'd also feel more comfortable if the CarMD had its basic

instructions right on the device, especially since there's key things to remember, like a) turn the ignition on but don't turn the engine on b) don't use its power switch while checking the car.