Engine Controls - Calibration Verification Number (CVN) Info.
Classification:
EC15-009
Reference:
NTB15-055
Date:
June 24, 2015
2005-2015 NISSAN VEHICLES; ECM REPROGRAMMING - SERVICE INFORMATION
APPLIED VEHICLES:
All 2005 - 2015 Nissan vehicles
SERVICE INFORMATION
After ECM reprogramming, the Calibration Verification Number (CVN) needs to be automatically calculated prior to State emissions testing (also known as Inspection Maintainence, I/M, or SMOG testing depending upon location). Allowing the vehicle to idle for 22 minutes will allow for faster CVN calculation. It is recommended that customers utilize this method if the vehicle needs to be tested for emissions soon after ECM reprogramming.
ACTION
1.
Ask the customer if he/she is planning to take the vehicle to an emissions test soon after ECM reprogramming.
2.
If YES, advise the customer to idle the vehicle outdoors for 22 minutes prior to emissions testing. (This 22 minutes is required during the same engine run cycle, but does not need to be continuous idle.)
BACKGROUND
When an ECM on an applied vehicle is reprogrammed for any reason, the CVN needs to be automatically recalculated. This process can take place while the vehicle is driven, but can occur faster if the engine is allowed to idle for up to 22 minutes (depending on model). Typically, the correct CVN is required for vehicles to pass state or local emissions testing, so customers are advised to idle the vehicle for 22 minutes if he/she is planning to take the vehicle to an emissions test soon after the ECM is reprogrammed.
