How Long Until ECU "Re-learns" After Reset?

Can't find a thread for this one. Had battery disconnected yesterday during stereo upgrade, so ECU data was cleared. Oops ... had scheduled Cali smog inspection today. Only 10+ miles driven since yesterday, so all ECU readings were in "not ready" state. In Cali, that's an immediate FAIL. I want to get this inspection out of the way, but can't until all ECU data is in "ready" mode.

Anyone have experiences in how many hours/miles of driving it typically takes to rebuild all ECU data to "ready" state? I understand that the answers will form a bell curve. Just trying to estimate how many hours & miles I need to drive it today to be in the ballpark!

Truck is 100% stock, 2006 Taco, Access Cab, 4-cyl manual. 94K miles. About 2/3 freeway & 1/3 local driving. Thanks in advance for your help!

 

Its not really X amount of hours/miles. Its driving conditions that have to be met.

Quote from the haynes techbook OBDII manual.

" A Typical OBD-II drive cycle consists of:
1. Cold start(coolant below 122 degrees F.
2. Five to eight-minute warm up and idle.
3. First acceleration to 55mph at half throttle with the air conditioning turned off.
4. First steady cruise at 55mph for three minutes.
5. First deceleration to 20mph.
6. Second accel, this time at 3/4 throttle.
7. Second steady cruise at 60mph for five minutes.
8. Second deceleration(without applying the clutch or brake pedal)."

Now there can be more too it as this book is from 06. But thats why they will tell you X amount miles/hours because you could possibly meet these drive cycles.

Easiest way to tell, go drive, then go to advance or autozone and ask them to check the drive cycle monitors status.

 

I recently had to do this on my dad's pathfinder with an OBDII gauge and this all depends on how you drive. From what I've noticed, it can take up to 3-4 days.

 

Thanks for the quick replies. Zach, that checklist is great! My inspection guy suggested driving in a variety of conditions, and said he's seen it take anywhere from 10-100 miles on average. I'm taking it out today with list in hand and will put it through its paces and then some. I'll report back on the results.

 

Yup yup,

Just remember that list is the basics out of the Haynes Techbook, so there can be a more involved.

 

mmm..learn something new everyday..thanks.

 

Yup yup, I just see this a lot, when a customer comes into my store to get a code checked and say something to the affect of "I have driven 400 miles, why isn't it done yet"??? so then I get to break out the manual and show them. Had a few come back same day and drive cycle monitors are complete in under 20 miles.

 

Most people just drive it for as many miles as they can not knowing there are certain driving conditions to be met.

 

Well thanks, Zach, your recipe did the job. With 44.1 miles of driving - about an hour total - the Taco had all the neccessary data and passed smog with no issues. The technician was surprised to see me back 24 hours after failing due to not-ready readings, and warned me that an hour of driving was very unlikely to have fixed the problem.

I passed and he was surprised, so I gave him a copy of those guidelines which I had followed in strict sequence - twice - and he was impressed. He was a young guy and probably not all that experienced but now he has a useful new tool.

So what did I learn from this? Don't do a full-on stereo overhaul the day before your scheduled smog test! (BTW, the stereo install came out great so it was worth it.)

 

Awesome happy to hear it!!! Good stuff

 

Hi guys....I'm a first time user ( my very first post, thank you). I have to mention, I am very appreciative of this opportunity!

To make it short, does the check list that was mentioned Jul 31, 2012 at 11:33 AM have to be completed in consecutive?
I left my Smog shop two hours ago, and just now found this thread. I have been driving in circles for the last three days per their request.

My question is, Do I need to start this check list first thing tomorrow morning starting from the very first item on list and continue down the list, or since I let it idle this morning for 10 minutes at start up, is that already checked off the list.

Thanks

 

i recently had to do a drive cycle \ readiness drive pattern for a camry. I did it all on one shot but the only way you can really tell is if you have a obd2 reader and check whats ready or not.

 

READINESS MONITOR DRIVE PATTERNS
Models:
All ’96 – ’02

https://www.toyotaparts.metro-toyota.com/READINESS_MONITOR_DRIVE_PATTERNS_T-EG02-003.pdf

https://www.toyotaguru.us/tacoma-pickup-truck-repair/monitor-description-yap.html