I need to pass emissions before the end of this month to renew registration. For some reason, my monitors won't go ready. In fact, I recently had monitors that were ready, now go to incomplete, despite driving 100+ miles.

2011 XJ supercharged with 60k miles

I have no check engine light on

I have no battery voltage problems and battery has not been disconnected

Car is completely stock

Why are these monitors losing status?

 

When monitors do not set many codes can't flag.

So you may well have the conditions for codes but it doesn't know which codes to flag - you may well be in Catch-22.

If you're lucky you'll have pending code(s). You will have P1000 or else your OBD tool isn't working right. Check which pending codes you have.

Next, use OBD live data to check every sensor you can for plausibility. You need data! Else life will be very tough, sadly.

 

Yes you should always have P1000 if they are not set and P1111 if they are all set? I don't see either code?

As you know the monitors have very specific ways to drive the car to get them to set. Also it can be extremely difficult to get them completed in normal driving. Here is a complete set of exactly what the car MUST see before it will set the monitors to completed. Also these types of driving will be dangerous on normal public roads. When I had a real bad one and just could NOT get the monitors to set I went far out in the country and followed these instructions. It's not easy to follow all those instructions either! Note it specifies temperatures and even things like how much fuel is in the tank!

How to set Jaguar Drive Cycle Monitors

Give these a try and report back?
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Several monitors do not just go incomplete all at once by themselves.

Something happened such as an OBD codes clear or battery disconnect.

What happened?

 

I went through a similar experience where one or more monitors would not complete and go into a ready state.
I even brought the car to the California BAR referee where they went through all the emissions systems as they looked for evidence of tampering. They gave me one year to find and fix the problem.I them brought the car to a local well respected Jaguar dealer and after two days of testing they determined that the main ECU was defective. After changing the ECU, all monitors reset properly and passed Smog.

 

Incredibly rare for that to be bad, always try everything else first!

 

calcarer what car was that on?
I ask because as JagV8 states ECM problems are really rare.
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It was on a 2012 XJL SuperSport with 42K miles.
Yes, taking it to the dealer was my last resort because I wrestled with the issue for over a year.

 

All,

What brand of code reader are you using?

I have a cheap reader that I keep in the '12, it doesn't read all codes and data streams, but, if I was ever to need it, would allow me to reset a MIL.

I keep a more sophisticated reader at home for the 575 and F-Pace that have better data streams, and more in depth analysis of codes. Perhaps your reader doesn't have the ability to read anything other than 'P' codes or basic parameters?

wombat