hello Jag experts, is there a procedure to clear the memory for the drive cycle procedure, without actually having to perform the drive cycle?
I have tried disconnectiong the battery, but the codes still remain.
I have a couple error codes: evap, misfire (fixed), 02 heater.
Car runs excellent, but I would like to clear these codes or fix them and it is hard to find a good spot where I live to do the drive cycle procedure properly.
The 02 heater, for example, there are four 02 sensors and I don't believe the error codes tell you which one is at fault?
I hate to have to replace all four.
thanks
The codes do tell you the specific sensor. Look up the actual number in the jag workshop manual or the codes PDF (each is free to download) or use forum Search as others have had them.
You're confusing drive cycle (explained in the same codes PDF just mentioned) and codes. They have almost nothing to do with each other but the main thing is you need to fix the fault(s) rather than go messing (which just causes you more hassle).
thanks for the reply, I am not getting DTC codes, these are MIL codes and there are no numbers associated with these error.
I am guessing these drive cycle error messages are left over from previous drive cycles.
I was hoping that I could clear out the drive cycle messages without having to do the drive cycle, but that defeats the purpose of the drive cycle test.
As JagV8 mentioned it sounds like you are getting confused with terminology and various systems. A 'drive cycle' means driving the vehicle for a significant distance at varying speeds to allow the car time to perform a series of self-tests. If all tests have completed code 'P1111' will be available. If the tests are not yet complete, code 'P1000' will be registered. If the car has any faults, these will be displayed also.
I've never heard of a DTC/MIL code that have no number associated with them.
Could you be more specific with what you are seeing?
Thanks Mikey and JagV8, - confused ? yes probably, perhaps even extremely confused.
I am not getting any codes, including P1111 or P1000.
I re-read my OBD code reader manual and I earlier incorrectly referred to “MIL error codes”, when I was thinking of the I/M monitors (Inspection and Maintenance).
My OBDII reader performs a “drive cycle verification test” . This test reads if there are any Drive Cycle Monitors that have not completed their monitoring cycle.
If a DTC code has recently been cleared, then a Drive Cycle must be performed to refresh the Drive Cycle Monitors.
It looks like there isn’t any way around not doing a Drive Cycle so that I can verify that the Drive Cycle Monitors have completed a new cycle.
I need to find an empty stretch of road outside of town to properly do the Drive Cycle test.
The front of the codes PDF gives details of the drive cycle to get the monitors to run. If any doesn't complete then something's blocking it/them. A cold soak overnight is needed for evap, tank not too full/empty. Etc.
If they still won't set, check for pending codes. Also check fuel trims.
Having forced a relearn by disconnecting the battery you've also unset the monitors. (In effect the emissions-related law requires this.)
If any won't set and there are no pending codes and the trims are OK then you're in a rare position that can happen and diagnosis will be a major pain. Hope you're not!!
If a DTC code has recently been cleared, then a Drive Cycle must be performed to refresh the Drive Cycle Monitors.
It looks like there isn’t any way around not doing a Drive Cycle so that I can verify that the Drive Cycle Monitors have completed a new cycle.
That's correct. Best read up on the specifics of what the car requires for the complete set of tests to be run. Example- the EVAP test will not initiate if the gas tank is above X% full or below Y% empty. If you've just filled up, it can take a hundred miles or so of driving before the level drops sufficiently.
