how long do i unhook the battery to do a full reset on the computer.
i heard there was 2 different resets one which takes about 15 minutes and a full reset takes 12 hours. is this true?
-matt

 

Interesting, I would assume the 12 hour reset would be the better of the two. I've never honestly had a need to reset my ECU like that, but I would assume the longer the better.

S

 

After about 15min your radio gets reset. If you unplug the battery for five min the radio retains all the settings. I had to reset my old ECU a couple of time my teacher said the majority of cars take about 30 mins at the most. My max usually only takes 15min then its reset.
I could be wrong, but for mine it works.

 

what are the bennifits of complete reset, and how do you know you should do it??

 

I dunno, my guess is it forces the ECU to "forget" its settings and trouble codes, which are stored on a PROM (programmable read-only memory) type chip. I would also assume that there are capacitors on the computer to save this information during a momentary loss of battery voltage. so leaving the battery disconnected for a good bit of time is necessary.

Then once all is cleared, the car is started and the computer resorts to its factory default settings, instead of compensating for a problem. from what I hear, the car will run rough for the first few miles until the system re-learns, so to speak, all of the sensors.

I've heard this works wonders on cars on a previously posted thread in this forum. I did this on my accord one time, left the battery disconnected overnight, and I actually did notice an increase in performance. (for a honda.) but I guess it's different with each car and each scenario. if you have a bad O2 sensor or EGR valve, this won't fix it. problem is, these 1st and 2nd gen maximas don't have a "check engine" light to let you know the ECU has detected a problem. you'd have to go by instinct, then read the diagnostic code from the computer when you suspect a problem.

Dan
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