Help! OBD II communication fail?

[golkhl]

Tried to get my car smogged and was failed due to OBD II communication failure. Went to two different smog shops on two different days, with the same result. My OBD port is getting power, because it is running my aero force gauge. I also hooked up my SCT, and it is working properly and there are no DTC's. Does anyone have any idea as to why my OBD is not communicating with the smog computer?

 

[BruceH]

Tried to get my car smogged and was failed due to OBD II communication failure. Went to two different smog shops on two different days, with the same result. My OBD port is getting power, because it is running my aero force gauge. I also hooked up my SCT, and it is working properly and there are no DTC's. Does anyone have any idea as to why my OBD is not communicating with the smog computer?

Have you asked your tuner? I don't know what the requirements are for communication but I know it's possible to reduce the number of checks to 18. IIRC stock has 254. I'm guessing that if the smog computer can't verify a certain number of functions it would think it's not communicating. Just a guess.

 

[golkhl]

Calling VMP in the morning, hopefully it will be something in the tune.

 

[Fullboogie]

Are you unplugging your Interceptor for the test, or are you using a "Y" adapter? The reason I ask is that every time I've tried to datalog with a "Y" adapter (so my Interceptor could continue running) I get a failure. I have to remove the adapter in order to establish a comm link to the laptop.

 

[golkhl]

Aero force is unplugged. Obd port has power, my sct device works, but the smog computer cannot establish a connection with my car. Took it to autozone today, and their scanner does not establish a connection either? I think bruceh is right, it is something in the tune. Talked to vmp today, hopefully we can figure it out.

 

[golkhl]

If the fuse(#61 20amp) was bad, would my aeroforce and sct still work?

 

[stkjock]

Has Nevada recently changed its inspection equipment or software?

 

[golkhl]

Not sure about the nevada software. If so, what can I do to get my car to ensure an obd II port connection?

 

[stkjock]

IDK, but some in NY are having the same issue and it seems the new system causes the issue with a tune.

 

[golkhl]

Checked the fuses, all looked good, replaced #61(under hood) and #8(kick panel) just in case. Talked to vmp, they said there is nothing in the tune that would be causing this issue. But they wanted me to take the car to autozone and see if their obdII scanner could communicate with my car. Same result, "failure to communicate". Next up is to reload the stock tune and see if it communicates. Any other ideas?

 

[429244]

IDK, but some in NY are having the same issue and it seems the new system causes the issue with a tune.

Can you elaborate on that? Did those cars not have an issue before the new system?

GOLKHL,
What year is your car? Check for terminal tightness on all pins at the OBD II port. For 2008 and newer, look close at pins 6 & 14.

 

[stkjock]

No, they passed in previous years. The new software seems to be 'hunting' more in the ECU.

 

[golkhl]

Thanks 429244, I will take a closer look at terminal pins 6&14. Waiting on my obdII scanner, so I can start to troubleshoot.

 

[golkhl]

Got my OBDII scanner today. Returned the tune to stock, and it communicated just fine; loaded an old Brenspeed N/A tune, and it communicated just fine. Loaded my VMP tune and it failed to communicate. Hopefully VMP can figure out what is going on with the tune.

 

[golkhl]

VMP made some adjustments to the tune strategy, and it now connects to my OBDII scanner. I have to put at least 100 miles on it, and then I will go back for a smog check.

 

[skwerl]

Glad he figured it out.

 

[stkjock]

VMP made some adjustments to the tune strategy, and it now connects to my OBDII scanner. I have to put at least 100 miles on it, and then I will go back for a smog check.

U don't need 100 miles. U need a driving cycle, RTM, should be in there.

 

[golkhl]

What do I need to do to complete a driving cycle?

 

[stkjock]

the cycle is in the manual (RTM = read the manual) I dont recall the entire process - however it can be done in less than 40 mins and 25 or 30 miles.

 

[AutoXRacer]

stkjock is correct... I have done it in a few miles. Its more cycles and operating conditions that matter more than mileage.