As my 1st line of offense, I thought I'd throw this out to my boating bretheren....

My daughter's 99 Hyundai Accent GS won't pass the state smog exam due to the onboard computer not finalizing the OBD Testing. A failure to communicate! All of the other parts of the test seem to pass with no problem, but when it comes to the final part, the PCM either fails (one station) or gets hot and shuts down (the dealer's test)..it won't communicate to the smog puter... consequently, it fails.... the local dealer wants freaking $720 for the part and $120 to install... So before I do extensive research and parts location on the net, does anyone know off hand how I can obtain a new PCM for a discounted price? Any links to parts houses that supply such items?

The dealer told me it's a dealer part, but need any help/info..

Thanks!

Nu2 - waaaiiiit!!! Don't do anything yet.

First, what is the vehicle's mileage? Your Hyundai's PCM is covered by a Federal 8/80 warranty.

Second, if the computer only fails to communicate, has someone checked all of the fuses? There is usually a fused B+ that supplies power to the diagnostic connector under the dash. Someone needs to check for power and ground at the connector. In your owner's manual, there is info on where all of the fuse boxes are and what the fuses protect.

Third, does the "check engine" light come on with the key on, engine off?

I have never replaced a Hyundai computer. I will do some research for you, just hold tight.

Thanks cny... The mileage is 59-60000, but the dealer said the warranty expired 1 year ago, 9/15/07. How can I be sure tho? This guy hasn't been real trustworthy, and this is a pretty reputable new car dealership in a large auto center.

Here's what's exactly happening. Both smog check station and the dealer ran into the same issue... the computer does work to a point. It reads and communicates up until the point of what's called the OBD (?) part of the test, then both times, it failed to send the final information.

The dealer called me about 4 hours after we took the car in and said the PCM is fine, and told me that some smog guys don't know how to 'turn the computer on' during the smog test. He convinced me to let him smog it, then he called me back an hour later and said the PCM appears to be shot; get's hot and shuts off and on intermittently at the OBD stage and won't finalize the test!. All wiring, fuses, and connections checked out ok..

Not wanting my daughter to pay that much money, I called a few other Hyundai dealers' parts depts in the area (including this one) and found this guy was less than honest with me. The part runs from 615-620, and labor at 95. When I called him on it, he couldn't believe his own parts dept was charging him more than what the same parts dept told me it would run!!! So I called another dealer, had them order the part, and we're set to go in next Friday....

If you can find out any other options, please let me know! I appreciate it!


Between A/C guys and auto mechs (present company excluded of course ) I'm getting run around the block!

Oops, forgot how the years are ticking by (on the 8/80).

Anyway, I am not familiar with your emissions testing procedures. I assume that you have both a tailpipe/IM240 type test and a scan-based OBDII test? I don't accept the diagnosis of the computer heating up during the test. This car has obviously been tested a year ago?

The research I've done suggests Hyundai has had some DLC pin connection problems. Techs have been successful in re-sizing the pins in the diagnostic connector when data bus communucations are a problem. You may want to run that by them.

Update... The other dealer originally ran into the same problem when he connected his computer to the car, before installing the new one, trying to get some codes and info. Said it worked for a while, then refused to communicate further. For kicks, after talking with a couple other mechanics, he took it to another lot owned by the same dealer, hooked it up and had no problems running thru all the diagnostics.. so he hooked it up to their smog machine and the dam thing passed!!! No problem. He had to charge for the smog (75.00, which is real high compared to the local shops) but no charge for diagnosis OR the PCM!
He couldn't explain it, nor could any of the other guys! Bizzarre. At least I know where to take 2 years from now!

As I thought, a new computer did not fix the problem. I really believe that the pins in the DLC are the problem, and probably the shop that got it to run had a less worn-out scan tool connector. Glad it's resolved!