how long after the battery has been disconnected and the computer is wiped clean will it take for the computer to register data? this has caused my vehicle to fail inspection

 

When you erase the memory you also erase the "Readiness Monitors" that indicate the computer has tested the various sensors and components in the emissions system. Some of these monitors require specific parameters be met before they will test and a LR Technician can likely know off the top of his head (like fuel level). Typically, if you run a tank of fuel through it everything will reset.

 

There are no time limits or distances, certain parameters must be met. I've driven over 500 miles since buying this POS and it still wont initiate because a. i cant go 50mph plus safely until I get the ****ing heads redone, and b. i woudlnt never been able to unless finding the follwing info: (below is a link with a few reset parameters) since i only drive it in bad weather to/from work, all under 25mph and stop and go traffic!

Drive Cycle Process for GEMS engine - Land Rover Forums : Land Rover and Range Rover Forum

 

thank you, thats a lot of help..time to go hit the roads I guess

 

The computer will register data once it has gone through enough "drive cycles", which are defined as the number of times the car is started and driven, and there is a time duration associated with the drive time, but I don't know what it is for Rovers. If you need them to reset quicker, you may be able to start it up, drive it around for a few minutes, park it, repeat. I know for my BMW, the magic number was 20-30, and if you are on this forum, there is a good chance that is who built your truck.

 

Generic OBD II "Drive Cycle"

Most OBD II ("On-Board Diagnostics II") diagnostic monitors will run at some time during normal operation of the vehicle.
However, to satisy all of the different Trip enable criteria and run all of the OBD II diagnostic monitors, the vehicle must be driven under a variety of conditions. The following drive cycle will (theoretically) allow all monitors to run on (??) vehicle. (Note: Drive cycle specifics vary by vehicle!)

-Ensure that the fuel tank is between 1/4 and 3/4 full.
-Start cold (below 86°F /30°C) and warm up until engine coolant temperature is at least 160° F (typically requires at least one minute; up to 3 minutes).
-Accelerate to 40-55 MPH at 25% throttle and maintain speed for five minutes.
-Decelerate without using the brake (coast down) to 20 MPH or less, then stop the vehicle. Allow the engine to idle for 10 seconds, turn the key off, and wait one minute.
-Restart and accelerate to 40-55 MPH at 25% throttle and maintain speed for two minutes.
-Decelerate with using the brake [or the clutch!] by coasting down to 20 MPH or less, then stop the vehicle. Allow the engine to idle for 10 seconds, turn the key off, and wait one minute.


Most states don't require ALL of the monitors to be ready for inspection. For example, I can have 1 in a not ready state in PA for something in the 2002-ish model year (which typically ends up being evap, because it takes the longest to run).