I recently purchased a new Nissan Altima for my wife. After some research I found this procedure for the Altima. Resetting and diagnosing ECM diagnostics codes problems.
I decided to use this procedure on my Titan. I left the gas cap loose, after an hour of diving the (SES) light was on. (Nothing like the glow of the SES light to raise your blood pressure) I used the below procedure and read the code of (0455); the ECM is indicating evaporative emission system leak detected. I retightened the gas cap and cleared the code. Use this procedure next time instead of disconnecting the battery cable.
ECM Diagnostics/ECM Reset procedure:
1) Sit in the driver's seat.
2) Turn the ignition key to the ON position and wait three seconds. (Do not start the car.)
3) Fully depress and release the accelerator pedal five times in less than five seconds.
4) Wait exactly seven seconds. Fully depress the accelerator pedal for ten seconds until the SES light flashes.
5) Release the accelerator pedal and start counting flashes to obtain the four-digit trouble code.
Long flashes (0.6 seconds) indicate the first digit of the code; count the blinks one through nine and write down the first digit. (Ten blinks indicates zero.)
The next three digits follow in turn in the same fashion except with faster blinks (0.3 second) and a 1.0-second pause between digits.
The ECM code repeats itself until you turn the ignition key to the OFF position, at which point the ECM resets itself to standard get-in-and-drive-mode.
Additionally, if you get four blinks of ten (0000), the ECM is indicating no malfunction.
You can look up the trouble codes at
You need to add the letter P to the four-digit code.
You can clear the code (and the annoying SES light) by holding down the accelerator pedal for more than 10 seconds while the SES light is blinking. When you release the pedal and turn ignition off the ECM erases the trouble code(s).
A built in code reader is definitely a plus on any vehicle. If this works the Altima and Titans it probably works on other late model Nissans.
Has anyone else used this procedure?