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Reseting the ECM (or ECU?)

2596 Views 31 Replies 14 Participants Last post by  Flavour
I thought it was Electronic Control Module ("ECM"). What is the ECU?

I've seen alot of posts regarding resetting the ECM (or ECU) by disconnecting the battery for 30 (or 60) minutes, then reconnect..start engine and let idle for 20-30 minutes. Then shut off, and your good to go.

But......the manual says simply pull out the radio fuse (7.5A) from the under-hood fuse box for 10 seconds then reconnect.

So what's the story. Pulling a fuse for 10 sec's seems alot easier than disconnecting the battery.
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ECU is electronic control unit.
I reset mine once but don't do it anymore as I lose all my settings on my Kenwood EQ



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93 VTEC 4WS & TC (JDM)
"and on the seventh day, God created VTEC"
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<font face="Verdana, Arial" size="2">Originally posted by U.K VTEC:
ECU is electronic control unit.
I reset mine once but don't do it anymore as I lose all my settings on my Kenwood EQ



</font>
So its the same thing..right? I guess the 5g manual uses the term ECM, whereas the earlier gens used ECU.
<font face="Verdana, Arial" size="2">Originally posted by Kool-Lude:
So its the same thing..right?
</font>
They are one and the same.

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93 VTEC 4WS & TC (JDM)
"and on the seventh day, God created VTEC"
Thanks U.K VTEC. Any thoughts on why some people would disconnect the battery instead of just pulling out a fuse for 10 seconds.

Maybe the fuse reset option is only on the 5g.

[This message has been edited by Kool-Lude (edited March 26, 2001).]
It doesn't matter which way you do it - fuse or neg. battery lead - both kill power to the ECU. Some people say do it for 10 seconds, others say 30 mins...
I don't know whose right or wrong.

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93 VTEC 4WS & TC (JDM)
"and on the seventh day, God created VTEC"
i just do mine over night. longer wont do any bad to it anyways. then in the morning in fair wether conditions i put it in neutral (i have an SS) and push it out of the garage. then i start the engine and just let it sit for like 30 mins or after i finish a meal or somthing.

i start it outside and on a fair day because i feel its important to have your car in a normally ventalated area in normal temperatures so your ecu will adjust according to those normal situations that u r most likely to drive in daily.
<font face="Verdana, Arial" size="2">Originally posted by Ng Luder:
then i start the engine and just let it sit for like 30 mins or after i finish a meal or somthing.

i start it outside and on a fair day because i feel its important to have your car in a normally ventalated area in normal temperatures so your ecu will adjust according to those normal situations that u r most likely to drive in daily.
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Interesting... I did mine in my garage, with the door open of course. Maybe next time I'll try it outside. Thanks for the tip.

Btw, last time I left my engine('70 Firebird)running and out of my sight while I was inside the house, the car disappeared. Yep, it was stolen... so I highly don't recommend this. Please learn from my mistake.


[This message has been edited by Kool-Lude (edited March 26, 2001).]
Use your spare key to start the engine then lock it up with your usual key


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93 VTEC 4WS & TC (JDM)
"and on the seventh day, God created VTEC"
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<font face="Verdana, Arial" size="2">Originally posted by U.K VTEC:
Use your spare key to start the engine then lock it up with your usual key


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Can't..5g has a "lockout prevention" system that won't allow u to lock the drivers door while engine is on.
Sit by the window then....with a baseball bat nearby.

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93 VTEC 4WS & TC (JDM)
"and on the seventh day, God created VTEC"
<font face="Verdana, Arial" size="2">Originally posted by U.K VTEC:
Sit by the window then....with a baseball bat nearby.

</font>
Exactly! The best alarm system is my bat.
haha, i didnt mean to just leave it out of site. i usually start it outside, then grab my self a cup of noodles or magazine and just sit in the car or somewhere in the garage a few feet from my lude
<font face="Verdana, Arial" size="2">Originally posted by Kool-Lude:
Can't..5g has a "lockout prevention" system that won't allow u to lock the drivers door while engine is on.</font>
You can do it with the key from the outside while its running. The system knows the difference between an accidental and an intentional lockout.

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N.I.T. RESULTS
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<font face="Verdana, Arial" size="2">Originally posted by Ng Luder:
i just do mine over night. longer wont do any bad to it anyways. then in the morning in fair wether conditions i put it in neutral (i have an SS) and push it out of the garage. then i start the engine and just let it sit for like 30 mins or after i finish a meal or somthing.</font>
30 seconds is enough time to cut power. 5 minutes is enough time to idle. That's enough time to re-set all your radio buttons.


Actually, the ECU is always making adjustments, so the only reason to re-set it is to clear the "history" it has accumulated prior to a modification. You can get by without resetting it after a mod, but the car might run funny for a little while.
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<font face="Verdana, Arial" size="2">Originally posted by Pete:
Actually, the ECU is always making adjustments, so the only reason to re-set it is to clear the "history" it has accumulated prior to a modification. You can get by without resetting it after a mod, but the car might run funny for a little while.</font>
This is true, but i read that the memory settings kick in when your engine senses something different..sort of a logic feature that protects the engine. I was concerned that by not resetting the ecu (& clearing the memory) it may just default to the previous memory settings..thus negating your mod. Please let me know what u think.

Regarding the door locks..I don't think I ever tried just stickin the key in and locking. I guess I always used the remote..which didn't work. Thanks, I'll try it.

[This message has been edited by Kool-Lude (edited March 26, 2001).]
Why not just get into your car, power lock your doors, crawl to the passenger side and manually open the lock, then get out. While the door is open, manually click the lock shut and close the door.

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SR20DE...Sorry
do what Pete said. i think that idle for 30 mins is a little extreme. it is said that its not good to leave your car at idle for long periods of time. also if your pull your battery cable leave it off and turn the ignition to on and start. that will "drain" any residual power in the car.
<font face="Verdana, Arial" size="2">Originally posted by Kool-Lude:
This is true, but i read that the memory settings kick in when your engine senses something different..sort of a logic feature that protects the engine. I was concerned that by not resetting the ecu (& clearing the memory) it may just default to the previous memory settings..thus negating your mod. Please let me know what u think.

Regarding the door locks..I don't think I ever tried just stickin the key in and locking. I guess I always used the remote..which didn't work. Thanks, I'll try it.
</font>
I think it depends on the mod. With a CAI the ECU would probably correctly adjust faster than it would with a new exhaust. It's designed to handle temperature differences, barometric pressure, etc. But you're probably right about a lot of other mods. Don't get me wrong, I would always reset the ECU if I had any doubts.

As far as the door locks go, I had three Acuras before I bought the 'Lude. They were the same way. I hate getting into a cold car after work, so about 10 minutes before quitting time I would run outside and warm it up--locked.

But then there was the time I left my RL running with the dogs inside--unlocked. Daisy hit the electric door lock button. Windows up. Sitting on empty. I couldn't teach her to roll down the window.

BIG GAME TONITE!!!

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HOW 'BOUT THEM TIGERS!!!
<A HREF="http://gotigersgo.fansonly.com/sports/m-baskbl/mem-m-baskbl-body.html" TARGET=_blank>
</A>
N.I.T. RESULTS
3/13/01 : Memphis 71 Utah 62
3/20/01 : Memphis 90 UTEP 65
3/22/01 : Memphis 81 New Mexico 63
NEXT: (3/27) vs. Tulsa IN NEW YORK CITY!!!

ESPN, 9pm EST
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