I bought my 2016 Jaguar XF 2.0 RSPORT with 80k miles on September 5th 2022, and for the first few weeks I had no issues at all. A few days ago, I had a ‘low coolant’ warning along with a ‘check engine’ light come on. I topped up coolant, but the check engine light remained on, then a couple of days later noticed the coolant levels had dropped again.

I booked an appt with my local garage, by which time the check engine light had turned itself off. They fixed the leaking coolant issues (replaced parts) and asked me if I would like diagnostics report nonetheless. The test revealed 19 faults within the Powertrain Control Module! I don’t have an extensive knowledge of the vehicle’s history, other than knowing it’s been serviced and passed its MOT every year.

The local garage have said that because there are no current warning lights on the dash it’s possible that these are historical faults that haven’t been cleared from the system. But that kind of uncertainty isn’t especially reassuring… They have now cleared it and recommend I bring it in to them the next time a warning light comes on and then they will be able to pinpoint the problem. The alternative is that I take pay for a thorough investigation of every possible fault.

I’ll list the record of faults below and ask if anyone here has experience of this and hopefully gather some opinions on what course of action I should take.


P006A-84 Manifold absolute pressure - signal is below allowable range

P026A-85 Charge air cooler efficiency - below threshold - signal is above allowable range

P229E-13 Nox sensor circuit circuit open

P22A1-17 Nox sensor circuit - voltage above threshold

P0299-84 Turbo supercharger under boost - signal is below allowable range

P0234-85 Turbo supercharger overboost condition - signal is above allowable range

P007C-16 Charge air cooler temperature sensor - circuit voltage below threshold

P0097-16 Charge air cooler temperature sensor circuit voltage below threshold

P0045-13 Turbo supercharger boost control solenoid circuit open

P026E-7B Charge air cooler coolant pump performance - low fluid level

P20EE-04 SCR Nox catalyst efficiency below threshold - system internal failure

P20EE-92 SCR Nox catalyst efficiency below threshold performance or incorrect operation

P20EE-97 SCR Nox catalyst efficiency below threshold component or system operation obstructed or blocked

P229F-28 Nox sensor circuit range - signal bias level is out of range

P23E8-00 EGR C Flow excessive detected

P0046-84 Turbo supercharger boost control solenoid - signal is below allowable range

P0046-85 turbo supercharger boost control solenoid - signal is above allowable range

P2598-73 turbocharger boost control position sensor a performance stuck low - actuator is stuck closed

P2599-72 turbocharger boost control position sensor performance stuck high - actuator is stuck open

Any advice is welcome, thanks.

 

Since the garage has now cleared all these stored faults, I agree with them that the best thing is to wait to see if the check engine light comes on again (I suspect it won't). But if it does, take it straight back to the garage for them to plug in their code reader and see what the fault is (or possible faults are).
I'm willing to suggest that the 19 faults won't all re-appear.
A "thorough investigation of every apparent fault" would take a long time, incur large labour costs and may not turn up anything, so in my view, it is not worth doing at this stage.

 

Good advice by chrisjp. Not all codes produce a CEL and many codes have no symptoms. That's why you should invest in a cheap code reader ($35 US) but make sure it allows you clear the codes (some don't!). If you get a CEL and a code pops up write it down and clear the code to see if it returns. For all you know those codes could have built up after 5 years of use (or not). Some codes have simple fixes (gas cap off or loose).

 

Welcome to the forums Simon01,

On any modern Jaguar, it is not unusual to find two or three pages of codes listed and it is neither necessary nor recommended to clear codes unless they are triggering a permanent MIL because it complicates symptomatic diagnostics and troubleshooting. However, as you have the list, it is inconsequential provided the date stamps for the events have been included. The order of events is often significant.

Most of those listed are 'out-of-range' which is frequently simply indicative of a partially discharged battery (these vehicle are VERY sensitive to battery charge and condition) or an infrequently used vehicle.

As you are in the UK, the vehicle will have OSH (OnLine Service History) if it has been serviced by a Jaguar Dealer or registered Independent:

https://osh.jaguar.com/

This details the service actions applied and can give a little more information if additional work has been required. DVLA history will detail any fail or advisory items:

https://www.gov.uk/check-mot-history

Even without service receipts, a lot of useful history can be compiled from these two sources.

Please read the guidance for new members ( https://www.jaguarforums.com/forum/n...ned-up-241802/ ) which answers many of the most frequent questions about getting started.

Enjoy the forums.

Graham

 

Thanks very much for all the helpful advice and information. I will be checking those resources, thanks Graham.