DII OBDII Drive Cycle - Getting your IM readiness monitors online

DarylJ

Well-known member
Apr 3, 2011
440
24
Doylestown, PA
This comes up over an over on a lot of forums, so I'm going to post it here and hope it gets indexed well enough that when people search they find it.

For those who don't know, after you "clear your codes" with an OBDII reader, your IM readiness monitors are in a "not ready" status. Different monitors need different conditions before they have made it through a full cycle so that they can either go to "ready" or throw a code for whatever reason is keeping them from going ready.

In most states with emissions inspection, you can have at least 1, if not 2 monitors offline and still pass the test (this is typically based on the age of the vehicle, and all DII2 fall into the same general category, at least in PA). The last one to go ready is almost always going to be Evap, and it can take a while considering you have to have less than about 1/2 tank of fuel before it can even consider starting the readiness test.

In any case, if you've cleared your codes and need to get these things online so you can get the truck inspected, "go out and drive" certainly works, but it's not terribly efficient. I happened to be at the garage today fixing their computer, and took the time to pull down some AllData and other info I've been meaning to stop by and grab. Among this is the drive cycle for all D2s (this says 2002, but I verified all years are the same):

2002 LAND ROVER DISCOVERY 4.0L 188 HP V8 (2) GAS-FI-N

ALL MONITORS - HIGHWAY DRIVE CYCLE - ALL MODELS NOT LISTED, ALL ENGINES
Notes:
1. This drive cycle is designed to simulate highway driving.
2. When instructed, vary speed smoothly.
3. Also perform the All Monitors - Urban (City) Drive Cycle twice.
Conditions:
1. Cold start.
STEPS:
1. Idle 20 seconds. Accelerate gradually and drive at 20-25 mph for 1 minute. Vary speed.
2. Drive at 25-31 mph for 35 seconds. Decelerate to 0 mph in 10 seconds. Idle 40 seconds.
3. Accelerate moderately. Drive at 20-25 mph for 20 seconds. Increase speed to 40-55 for 85 seconds, then decelerate to 0 over 50 seconds. Idle 15 seconds.
4. Gradually increase speed to 36 mph in 35 seconds. Decelerate to 0 in 15 seconds. Idle 10 seconds.
5. Accelerate to 30 mph and decelerate to 0 over 25 second period. Idle 20 seconds.
6. Accelerate to 36 mph in 20 seconds. Drive at 35 mph for 20 seconds. Decelerate to 0 in 15 seconds. Idle 5 seconds.
7. Accelerate to 26 mph and decelerate to 0 in 40 seconds. Idle 15 seconds.
8. Accelerate to 27 mph in 40 seconds. Decelerate to 0 in 8 seconds. Idle 25 seconds.
9. Accelerate to 26 mph and decelerate to 0 in 35 seconds. Idle 15 seconds.
10. Drive in stop-and-go traffic for 1 minute, reaching 25-30 mph twice, with no complete stops.
11. Drive at 20-30 mph for 2 minutes and stop. Vary speed. Drive at 20-28 mph for 2-1/2 minutes at varying speeds. Stop. Idle 30 seconds.
12. Accelerate to 28 mph and back to 0 in 50 seconds. Accelerate to 20 mph in 10 seconds, drive at 20-27 mph for 20 seconds and decelerate to 0 in 10 seconds. Idle 15 seconds.
13. Accelerate to 23 mph and back to 0 in 20 seconds. Idle 10 seconds. Accelerate to 22 mph and back to 0 in 45 seconds. Idle 10 seconds.
14. Accelerate to 25 mph in 30 seconds. Drive at 23-28 mph for 25 seconds. Decelerate to 0 in < 10 seconds.
15. Idle 25 seconds. Accelerate to 22 mph and back to 0 in 30 seconds.
 

Some Dude

Well-known member
Feb 12, 2009
1,590
0
Boise, ID
These things are such bullshit. How are you going to do all that on a public road? You'd be crashing into cars and running lights all over the place.
 

DarylJ

Well-known member
Apr 3, 2011
440
24
Doylestown, PA
That really depends on where you live, now doesn't it?

I can easily do this driving around my house anytime other than 7-9 and 4-6. And you don't have to do it exactly like that, without doing anything else in between (like stopping for a light, driving off to find another road, etc).
 

JohnB

Well-known member
Oct 18, 2007
2,295
12
Oregon
I puked a coil pack last month and after clearing codes my cat and 02 will not go into ready mode. No codes are showing up and have put at least 700-1000 miles on it.
Same bloody mileage as always 14-15 mph. Usually readiness happens quick.
Maybe I will try the above drive cycle test. This would require me sleeping in the Rover on a country road, waking around dawn and with a stop watch in hand some how try to pull off the above test. :eek: Bet I get pulled over by one of the local constables.