How many miles to drive until it will smog?

[rhd]

I have a '98 V70XC. I cleared a code after repairing the problem, and have driven more than a hundred miles since reconnecting the battery.
Today I took it in to smog, and the tech said I had to drive it more, until it had run all its tests.
How may miles does it take to reset the OBB-II system?
Thanks.

[Ozark Lee]

It is less of a matter of miles than it is a "drive cycle". The monitors are terribly tough to get to the ready state and Volvo published a drive cycle that should help.

https://www.matthewsvolvosite.com/forums ... hp?p=56234

...Lee

[rhd]

I found this on another Volvo forum site. It should be helpful when someone else has the same problem in the future.
It was posted there after being copied and pasted from Volvo.

What are Readiness Codes?
As required by Federal and State laws, there are various antitampering
devices installed within the OBDII system. These
devices will indicate if someone has attempted to alter the
emission control system or has tried to erase any stored
malfunction information.

Part of the anti-tampering system is a "Readiness" check.
The "Readiness" check assures that all of the monitors and
sensors have completed a number of driving cycles without a
problem. The systems are checked and return a signal to the
inspector that the OBDII system is Readiness – OK. In other
words, it's OK to continue with the inspection.
Under some unique circumstances, the Readiness Code
may not read OK, even though the emission control system
has not been tampered with and is not malfunctioning. These
circumstances may include the following:
• A service where the battery was disconnected and the
vehicle has not been driven enough to allow the system to
cycle through all of the readiness checks.
• Vehicle is typically driven for only very short cycles, less than
20 minutes.
• Vehicle is typically driven for only uninterrupted highway
cycles where there’s no period of prolonged engine idle, such
as standing at a stop light.

Can I Reset the Readiness Codes Myself?
In some cases, YES. How easily the car will reset may be
determined by the model and the age of the vehicle. Older
model years, and cars with high mileage (100,000 miles or
greater) tend be more sensitive to this situation.
However, there is a generic driving cycle that has been very
helpful in resetting the Readiness Codes. It is a driving cycle
that can be driven over local roads and highways safely. Driving
this cycle does not guarantee that the Readiness Codes will be
reset but it has been very helpful in most cases.
Part of all new car certification requires that the Readiness
Code monitors run to completion after following a standard
specified driving cycle. The drive cycle represented below, is
similar to this standard. You may find it necessary to drive
this complete cycle twice. An adequate cool down period
between the two separate driving cycles – generally 30
minutes – will assure that the various readiness monitors are
reset for the second driving cycle.

1.) Accelerate 0-50 MPH within 30 seconds
2.) Maintain 45-50 MPH for 20 minutes without using cruise control
3.) Park car turn of A/C idle for 5 minutes
4.) Accelerate 0-50 MPH within 30 seconds
5.) Maintain 45-50 MPH for 20 minutes without using cruise control
6.) Shut off car and allow to cool for 30 minutes before repeating cycle ( in some cases the car requires two cycles)

[erikv11]

The drive cycle Lee posted is much shorter, I would check it out first.