Joe Weinstein

Hi all,
I have to get the car smog-tested to register it, and the smog guy said the car ECU got wiped during the last shop visit, and I need to do some 'drive cycles' to get the ECU systems ready for test. I googled it, and didn't find a cayenne protocol, but did fine some posts claiming that 911s need some sort of orchestrated mother-may-I driving pattern, and others that say you just need to drive it enough... Or is there something the dealer can/should reset?
Thanks!

garrett376

A PIWIS2 (and likely 3) can run a "short test" which gets all of the readiness monitors into READY status within a few minutes, with no driving needed. So yes, a dealer should have no problem doing it.

Archimedes

Don't know about the Cayenne, but on the Carreras, if the battery gets low/drains, there is a sensor that will reset (ECT Sensor IIRC) and all you need to do is drive the car on the freeway for about 20-30 minutes at normal speeds to get it to reset. I had this problem when smogging a new car I bought out of state that had been sitting, drove it around for about 20 minutes and it reset.

pdxjim

I posted below the same diesel problem. Took it to the dealer today for replacement rear brake lights. I thought it was a simple bulb replacement not! I asked about the "unready" status on my OBD Summary from Shell Fitcar APP. They checked out the summary and concurred with the facts stated. Said they did not want to clear the codes as I would then have to hope that the various Sensor Status Codes would come back "complete" the next time I tested. So, they said to drive it a couple hundred miles and bring it back. Quite a PITA to accomplish what used to be a simple procedure.

slavie

There are 8-12 monitors depending on a car and whatnot, and each of them has a different "drive cycle" that has to be completed for the monitor to be set as complete. If you knew which monitor was not set, you would be able to look up the setting criteria for that particular monitor and drive it to complete the test. Otherwise, you have to drive a bunch waiting for it to meet all the criteria through your every day driving.

Any time you reset a check-engine light the monitors are automatically reset. This is done so that you could not just reset a light and drive in for inspection - by driving to set monitors, the car does a thorough test.

On more recent cars, some check engine lights cannot even be reset at all. You have to drive the vehicle until the vehicle itself determines that the fault has been removed and clears the light. Again, you can thank shady dealers and mechanics trying to play the system for this.

pdxjim

I did a 120 drive the other day and checked again and all systems were complete. I was able to renew online my plates. Just takes time as noted above for everything to be faultless.

Joe Weinstein

I found a 911 drive-cycle protocol which I followed, and then the car was ready for smogging, and passed. The protocol was a bit annoying... idle 3 mins, 1/2-3/4 tank of gas, 4 mins 20-40mph, then 15 miles 40-60, then idle in drive 4 mins, then again 4 mins 20-40mph, then 15 miles 40-60, then idle in drive 4 mins. I actually had to consult google maps to see where I could do this without stops etc...