Reset Ecu Procedure

[Cyprus]

i want to reset my stock ecu in my Series II r33 Gts-t so it learns that i have changed my dump pipe / front pipe / & cat back .. and upgraded smic ..

how do i do it and what is the procedure step by step?

plz help .. much appreciation

[R31Nismoid]

Please read the sticky threads

They are there to help you!

http://www.skylinesaustralia.com/forums/in...?showtopic=2879

That was one of the links, all the detail is there for you.

[Darkboy]

Disconnect your battery, then whilst disconnected push the brake pedal hard down and hold for a few secs then release.

Reconnect the battery. Now its reset.

[GtstCoupe]

Ok very easy, disconnect you battery negative will do

and leave the door open so that the light is on and once you

take the neg. off the batt go and pump the brake

a fewtimes or just try to turn sumstuff on like centrallocking etc

just to drain allthepower from the caps in theecu and in the car and

then give it a fewminutes and simply re-connect and start car, go for a drive and alldone. :-)

[217/r33]

Ok I just so don't believe in that method

1* Remove fuse panel on driver side

2* Locate the plug like in the picture below

3* Find a paper clip, Turn on the reds (don't start) Short circuit the 2 wires for 2 seconds. (WIRE COLOURED BLUE/BROWN)

Your ECU is now reset and in diagnostic mode. If you get 5 fast flash's and 5 slow flash's with your engine light all you sensors are fine. If not refer to the code list below. AND YOUR DONE !... With no stupid battery terminal removal.

Cheers,

Alex...

Ok very easy, disconnect you battery negative will do

and leave the door open so that the light is on and once you

take the neg. off the batt go and pump the brake

a fewtimes or just try to turn sumstuff on like centrallocking etc

just to drain allthepower from the caps in theecu and in the car and

then give it a fewminutes and simply re-connect and start car, go for a drive and alldone. :-)

[rob82]

i want to reset my stock ecu in my Series II r33 Gts-t so it learns that i have changed my dump pipe / front pipe / & cat back .. and upgraded smic ..

how do i do it and what is the procedure step by step?

plz help .. much appreciation

Nissans have no LTFT (long term fuel trim) capability, they are a dynamic system so only STFT (short term fuel trims) are learnt which means every time you power off it loses any of the changes it may have learnt. So in doing a reset it will do sweet f**k all in terms of fuel metering and most likely do nothing at all with ignition - but feel free to reset maybe it will fix you big end knock!!!

[O.I.C Napster]

Nissans have no LTFT (long term fuel trim) capability, they are a dynamic system so only STFT (short term fuel trims) are learnt which means every time you power off it loses any of the changes it may have learnt. So in doing a reset it will do sweet f**k all in terms of fuel metering and most likely do nothing at all with ignition - but feel free to reset maybe it will fix you big end knock!!!

Ok now im confused, does anyone have proof or anything saying that disconnecting the battery or shorting out the fuse thing actually reset the ecu?

i know its a long thread that people have been reading but does any of these actually work?

I aint no mechanic but yeah im sure more then just me would like to know.

Cheers M

[fr0st]

Ok now im confused, does anyone have proof or anything saying that disconnecting the battery or shorting out the fuse thing actually reset the ecu?

The ecu contains form of memory that retains its state after the power is removed. No flash, no eeprom. There is no possible way it can store fuel trim maps between drives without constant power, which I'm quite sure that it doesn't because power is removed when the car is switched off.

I'd be looking elsewhere for your problem if you have one

[TSL]

There is no possible way it can store fuel trim maps between drives without constant power, which I'm quite sure that it doesn't because power is removed when the car is switched off.

Nissan ecu's do have a constant power feed direct from the battery.

I think people are grossly overestimating the capabilities of the ecu's self learning.

[SKY 34]

The ecu contains form of memory that retains its state after the power is removed. No flash, no eeprom. There is no possible way it can store fuel trim maps between drives without constant power, which I'm quite sure that it doesn't because power is removed when the car is switched off.

I'd be looking elsewhere for your problem if you have one

power still flows even after you switch off the car, that is why if you leave your car battry in without switching on the car for a month or so the battery will be drained

although how does resetting the ecu makes it re-learn? I think the ecu will retain its memory, just like your computer, you switch it off, pull the plugs, you don't find all your data lost..

if the ECU has self learning and STFT, wouldn't fitting the exhaust system automatically be recognised? so why bother to re-set?

[Munkyb0y]

Nissans have no LTFT (long term fuel trim) capability, they are a dynamic system so only STFT (short term fuel trims) are learnt which means every time you power off it loses any of the changes it may have learnt. So in doing a reset it will do sweet f**k all in terms of fuel metering and most likely do nothing at all with ignition - but feel free to reset maybe it will fix you big end knock!!!

^^^

that's what i've been told by a couple of tuners.

apparently, any learning that may occur will basically happen each time you start the car, although it's minimal to none. The ecu just isnt that smart.

[drewbear]

Unbelievable ....... my R33 hasnt started for 2 months ..... replaced the startermotor and still no crank ..... did the ecu reset and started first pop ... thx :-)

[Dose Pipe Sutututu]

Nissans have no LTFT (long term fuel trim) capability, they are a dynamic system so only STFT (short term fuel trims) are learnt which means every time you power off it loses any of the changes it may have learnt. So in doing a reset it will do sweet f**k all in terms of fuel metering and most likely do nothing at all with ignition - but feel free to reset maybe it will fix you big end knock!!!

I was under that impression too, it is a closed loop system and changes dynamically to achieve stoich. Timing is a fixed map and only retards on knock detection.

[Manuel Kasko]

Unbelievable ....... my R33 hasnt started for 2 months ..... replaced the startermotor and still no crank ..... did the ecu reset and started first pop ... thx :-)

Probably a loose battery terminal

You fixed when you did the reset

[51NNA]

Haha ECU has no control over the starter it would of been a loose terminal, but im glad it fixed it!!