You have certainly figured out that your 2002 Hyundai coupe V6 Gen3 has a problem : when connecting a diagnostic tool on your OBDII port, it can't have access to the ECU. It brings numerous troubles, one of them being that CEL codes can't be read. So you just have to guess what the problem is with your car, and it's not always obvious...
I have personnaly done a lot of research about this. Here are the results :
- Whatever the diagnostic tool and the software you use, it's always the same. Even with a Hyundai scan tool. You can't have access to the ECU datas...
- Hyundai has published a note a few years ago about the OBDII port on 2002 gen3 : we have to wire the missing pin 5 in the OBDII port to the ground cable of the pin 4 wire, and it would work. Well, in fact, no, it still doesn't work. It will now let you have access to airbags datas, but you'll still be unable to access to the ECU. And Hyundai doesn't know that.
- The cause of this ? We don't know exactly. The 2002 is quite different from the later Gen3 : the ECU is 2 bits (it's 4 bits on later Gen3), the lambda sensors are wideband instead of narrowband, the OBDII port is not cabled as it should...
- The problem seems to be worldwide and touching all 2002 Gen3 V6. I know 14 owners of these cars in France, all have the problem. I've met on forums a german and a canadian who had the problem too.
The consequences :
- You can't read CEL codes ;
- You can't read long term fuel trims, so if you're a hardcore user wanting to tune the air/fuel ratio perfectly with a piggyback, it's a problem ;
- When you're trying to pass emissions tests, the default will be noted on the certificate (in France that's the case) ;
- you can't use NGM handheld ECU reflash tool
- When you have a problem with the car and go the hyundai dealer, you'll sometimes meet an asshole who will not bother to listen to you, and will keep on telling the ECU is f***ed up and is causing the trouble, and must be changed (1500€...). Actually a friend of mine has this problem : his 2002 V6 gen3 won't start, i think it's just the immobilizer ; but the mecanic keep on telling the ECU must be changed because he can't have access to it...
So here in France we have decided to do something at last, and we have agreed that each hyundai coupe owner having this problem (we're 14 at the moment) will send a mail to Hyundai France to complain about this, explain the problem, and ask Hyundai to inform all his dealers and mecanics about it. If you could do the same with Hyundai England, that would be interessant, too. We're contacting all the european hyundai coupe forums about this.
Sorry for the bad english