readiness monitors won't set

just found this site- looks like a great resource, I've been watching the scanner danner videos for a while. 12 JEEP WRANGLER 3.6 manual trans. We can't set readiness monitors, no DTC's/ no CEL. Driven a few hundred miles, tried our best to do proper drive cycle, but impossible on the roads here. replaced thermostat & took to 2 jeep dealers. Had PCM reflashed, replaced thermostat, all PID's look pretty good & all sensors react properly to input. Only monitors that set are misfire & CCM. Have watched both cat & evap (after doing a function test) set & then almost immediately unset. No TSB's, though there is one for this issue on older jeeps where you cut & splice wires under the PDC, but this car has a different TIPM design. We're at a loss, thinking about throwing a PCM in, but that's a $700 guess. Anyone run into this before or have any ideas?

Is the cold ECT and IAT within 18⁰ F?

According to SI, it can take one to two weeks for all the monitors to complete.

Evaporative Emission System Leak Detection with Purge Monitor
This monitor requires a cool down cycle, usually an overnight soak for at least 8 hours without the engine running. The ambient temperature must decrease overnight - parking the vehicle outside is advised. To run this test the fuel level must be between 15-85% full. Criteria for EVAP monitor:

Engine off time greater than one hour .
Fuel Level between 15% and 85%.
Start Up ECT and IAT within 10°C (18°F).
Vehicle started and run until Purge Monitor reports a result.

NOTE:
If the vehicle does not report a result and the conditions where correct. It may take up to two weeks to fail the small leak monitor. DO NOT use this test to attempt to determine a fault. Use the appropriate service information procedure for finding a small leak. If there are no faults and the conditions are correct this test will run and report a pass. Note the Small leak test can find leaks less than 10 thousands of an inch. If a small leak is present it takes approximately one week of normal driving to report a failure.


Catalyst / O2 Monitor
The Catalyst and O2 Monitor information are acquired and processed at the same time. Most vehicles will need to be driven at highway speed (less than 50 mph) (73km/h) for a few minutes. Some vehicles run the monitor at idle in drive. If the vehicle is equipped with a manual transmission, using 4th gear may assist in meeting the monitor running criteria.

Engine RPM between 1200 to 3000.
Enginetemperature greater than 70°C (158°F)
Engine run time greater than 92 seconds
MAP between 10 - 20 kPa (7.5 - 15 Hg)
Vehicle speed between 20 - 70 mph (29–103 km/h)

EGR Monitor
After the vehicle has reached the below conditions and during a throttle decel the EGR monitor will run.

Engine RPM between 1375 - 2500
Engine temperature greater than 70°C (158°F)
Engine run time greater than 125 seconds
Vehicle speed between 25 - 70 mph (37–103 km/h)

O2 Sensor Heater Monitor
This monitor is now continuously running once the heaters are energized. Pass information will be processed at power down.


Mis-Fire Monitor
The Misfire Monitor is a continuous two-trip monitor. The monitor uses two different tests/counters:


NOTE:
The Adaptive Numerator must be learned before the PCM will run the Mis-Fire Monitor. The PCM updates the Adaptive Numerator at every key-ON, and is relearned after battery disconnect. The Misfire Monitor will not run until the Adaptive Numerator has updated since the last battery disconnect. If the Adaptive Numerator is equal to the default value then the PCM knows that the Adaptive Numerator has not been learned and does not permit the Misfire Monitor to run. If the Adaptive Numerator exceeds a calibrated percentage, the PCM sets a DTC for CKP NOT LEARNED and illuminates the MIL.

200 Revolution Counter - Looks for misfire that can cause immediate catalyst damage.
1000 Revolution Counter - Looks for misfire that can cause emissions to increase 1.5 times the Federal Test Procedure (FTP) standards. This test must also identify misfire percentages that might cause a “durability demonstration vehicle” to fail an Inspection and Maintenance Program tailpipe emissions test.

toms9106 wrote:

No TSB's, though there is one for this issue on older jeeps where you cut & splice wires under the PDC, but this car has a different TIPM design.

Was the TSB for loss of B+ keep alive power to the PCM? That might be what's wrong with this. Look for miles since, or warm ups since, MIL clear PIDs to see if they're counting up or resetting to zero after the key is turned off for a while.

Another thing is the fuel level working and the tank between 25% and 75% full?

Matt T, I don't see a TSB for that in Alldata SI.

Surprisingly enough, the TSB list is quite small, BUT there is a TSB for PCM upgrade that mentions EVAP small leak detection though!!!

The sad truth is if you do not meet the drive cycle requirements (which has conditions (like engine temperature and fuel tank level) in addition to those when the car is moving (driving)) your monitors for CAT and EVAP will never pass, not to mention they will have to pass on two separate trips each meeting the same drive cycle requirements, described as a two trip monitor (which really should be called a two drive cycle monitor, because the label trip is not specific enough as to what is required).

You hear this a lot from the smog guys; just drive normally and you will eventually pass your monitors. Well maybe yes and maybe no, because if your normal driving does not satisfy the drive cycle your monitors will never pass, and if you take your car in to get tested you will pay money to fail.

When OBD-II was created there was a generic OBD-II Drive Cycle Chart that would describe how the different OBD-II systems needed to be tested in order to pass. However, the EVAP monitor was given a waiver due to the different OEM design approach. When this grace period ended I think around 2002, the EVAP monitor would now have to pass as part of meeting inspection, although the requirements for passing can be OEM specific. So what this means is you really have to find out what your vehicle OEM sets as the needed drive cycle requirements and then satisfy them.

I have many vehicle diagnostic tools, but for monitors I use an Innova 5610 which primary purpose is to quickly establish communication with the PCM and indicate what monitors have passed. In the worse case scenario, I can drive for a week or more and not pass the CAT efficiency monitor. My EVAP will not pass if my tank fuel level is not between 1/4 and 3/4 full.