Thanks Mark. I hope we didn't lose everyone and I will test more after the family get together and holiday. It's too bad I couldn't drive the Jaguar with family coming to town.

 

If PATS is stored in RAM it shouldn't matter if it is swapped as it is non persistent in the system and resets each startup?

Meaning it will test every sensor on startup and clear these "codes" that suggest a fault once they no longer exist given the actual part is intact and functional. If a piece is missing it just respond with code 24...

I think we would all love to understand this better.

 

I've retired my technician coveralls for quite a while...Put on a tie in 1999 and a suit in 2009 as my career has progressed.

I do have to keep up with current technology as it helps me keep some credibility with my Service Managers..

I will go out on a very stable limb and tell you..If you change the PCM/ECM you will absolutely have to have access to either a WDS or IDS/SDD software to program the module to your vehicle. The only way we do this in the shop is called a PMI process. In short it basically inhales the data from anything on the particular CAN bus you are working with and programs the old data to the new module.

All that aside..reboot?

What happens when you stick your key in the ignition and try to start? If we have a PATS issue the light on the dash with flash in a very rapid mode..indicating someone is trying to steal the vehicle.

 

Dr JagerCola

I have followed this thread for why I don't know.
. I have made only one comment , complimenting Karl , Jag v-8 and others for sticking it out with you. which seemed to highly offend you.
I stand by my original statement. Reading this has been like watching a wreck happen in slow motion. Only now I've seen too much horror and must look away.
I have refrained from technical comment as I stated before because I can determine by reading the thread that you have been getting solid good advice already from several qualified commenters who are well meaning with the clear intent of helping you despite yourself.

I again qualify my comment by saying I mean you no intentional insult. But I must say it is painful to read your technical, wild goose chase ,off tangent rants while at the same time ignoring and arguing against solid advice from clearly competent technicians .
You said yourself you distrust and have an issue with mechanics . Clearly that is true.

So I don't understand why you seek their advice on this website forum only to disregard everything they have to say . They clearly have no financial agenda , they are not trying to sell you anything.

Out of sheer good will for strangers, and the love of the cars they offer a lifetime of experience to assist you. Its hard enough to help diag a vehicle without being there. But you are making the process excrutiatingly painful for the people trying to help you.
You are attempting procedures that veteran techs are warning you NOT to do. You are on your own course of pursuit , that's fine . You are the equivalent of a patient performing his own brain surgery by referencing you tube videos without completing a basic diagnostic physical .
Yes its your thread and your car Good Luck ! That is not meant sarcastically, but I assume for others with resignation.
You can lead a battery to the electrons but you cant make it take a charge, lol.

There is a Diagnostic mantra in this business. Its the K.I.S.S. method." Keep it simple s t .p..i.d "

I have two kinds of advice .Friendly advice and professional advice. Professional advice is $ 100.00 an hour Friendly advice is free.
My friendly advice is ….see a professional.
Listen to the advice you have already received from well meaning , experienced , competent jag techs. Best R

 

Okay, sure. I'm not competent to make a decision and this is brain surgery. A brain surgeon who didn't even check the electrical guide or resistance to the switched ground... This reminds me of my youth while playing baseball and we had a bad call by an inexperienced umpire. Our teams parents/coach brought a rulebook on the field to contest the call and the umpire threw him out, for breaking the rules by bringing to book on the field... You won't look stupid if you ignore the facts and toss them out.

Please don't waste my time with that nonsense. It's take humility and humbleness to solve technical issues and so it doesn't matter how much experience they have if they lack the ability to admit they don't understand the electrical system, or how to repair a computer etc. If people didn't hate getting their hands dirty these type of mechanics wouldn't make minimum wage for their misguidance. Ronn, you wouldn't keep charging hours or wasting MY time if you ignore strong evidence suggesting a more correct course of action and/or toss ideas out because it's not your strong suit. For example, not every wire goes through a fuse and we can't seem to even recognize that with JagV8 and he gets very upset and defensive whenever the idea of the solenoid circuit damaging the ECM/PCM is suggested. He's going to be wrong and then it will be a bunch of excuses about how he shouldn't be expected to know that and it wasn't his fault and how he never said anything about it or claimed to be experienced. Free advice. Yes, let's entertain his cognitive dissonance and pass blame instead of just answering the question about powering past a solenoid to the ground switching on a PCM and whether that damages the unit and if you can't explain how or why we have solenoids or why it would or wouldn't damage the PCM then your experience isn't worth much and your guess as good as mine.. in which case, if I were a professional I would leave the ego about who is right or wrong out of the equation and do some research or just stay out of it.

We are right back were we started and we should continue by acknowledging to check resistance or volts at the "customer" (solenoid) and when I present the correct method in the form of an equation it is cast out. There's never been a time in my entire career that a professional has rejected another teachers work due to their low intelligence without even trying to provide a more accurate equation. If it were long devision and taught incorrectly, you could say something like you shouldn't carry the remained if you BELIEVE you are factually correct but I'm just told "no, your PCM is fine" while I'm looking at very strong evidence from multiple sources (3) that say it's not.

No offense, but maybe it's time for me to be a little assertive back about this type of bias if people are picking a winner based on who is more forceful in their approach. It's generally not the way I play but I can set aside the manners and do the ego thing as well as any man.

I'm not trying to put a new computer in the Jag and having new VIN or memory. I'm referring to the main Micro controller and 2 memory ICs from the video and simply loosing power while they are unplugged and changed to a healthy board. I think Mark has good intentions and knows this and so let's not confuse others and at least try to acknowledge the solutions I'm suggesting, regardless of if any professional mechanics would be more creative in their problem solving and try it my way. Where's the irony if my having respect for your strengths while my ability to problem solve and think critically is cast out in favor of antiquated process? I spent a lot of time and money on education so don't mind me if I honor and respect my ability to do a little of your brain surgery and give this a shot. Working with people and ideas from people smarter than you is part of the job in any profession and so I would say to Ronn and JagV8 to get used to it.

We've spent appropriate time entertaining new batteries and buying the right code readers and now there's a high likelihood I need to act on the information of outside sources in order to get my car back on the road. I would hope you can appreciate the openness to these sources or debunk them with evidence.

If you think I will fry the computer by having it repaired then that is noted. I've found such a repair to be reasonable risk until further notice. I'm fully prepared to buy a new clean PCM or scrap the car in the quest for knowledge.

XJR RONN, you only come onto someone's post to pat the back of the "helpful techs" and twist my metaphorical arm to follow his guidance blindly. If they are doing a good job they don't need your support and they wouldn't want your tag teaming the original poster to prove their correct premise. Time has a way of proving people right and the good ones understand the relationship. These are the tangents you speak of and the entire process is ignoring the "customer" and JagV8's posting reads like someone with emotional baggage needing to be right. Please hold his hand on your own time and we don't need that kind of drama to discuss the technical potential of various solutions and ideas. Or maybe I'm at fault and that's why you guys hang out here and I need to put the repair of my Jag after the interest of people and or discuss it elsewhere. I can see that possibility as well and I'm open to it.

If you're here to explore solutions, here's where we are:

Scanning the ohms at the solenoid to PCM.

Investigating the possibility of a burnt out pin or one of the (2) transistors I'm told go to each output on the board...? Booting it up after should find a matching VIN stored in the modules and it would be identical to the original computer due to the replacement board and parts having no memory of where they exist. There's no need to flash it again from what I've witnessed and it would be analogous to putting new ram and processor into a new computer without a broken keyboard or screen. The first computer I took apart this seemed like an extremely dangerous and daunting task as I imagine it is for some of you.

In the case of a few modern computers and especially laptops this can't always be done and may cause some confusion around doing such a swap in the PCM of a vehicle. I know the MacBook Air I use at work has memory that can't be upgrades and is integrated into the board. As far as computers go, a cars memory and controller is hardly a problem for a qualified computer repairman. Just look at the size of the box it comes in to be sure they left plenty of space to swap things out with the most basic tools and it wouldn't be out of the question for the engineers to put this one at the very bottom corner next to the handbrake knowing it could possibly short due to the sensitive nature of needing ground switching to a variable valve solenoid that controls the instantaneous oil pressure and other timing of this modern vehicle. The reason we have solenoids is to prevent heavy wires in ignitions systems or to allow control and switching by the computer with a simple grounding wire. But, that also implies we do damage if we mess with it due to the lack of resistance anywhere between the 12v power source and ground (bypassing the solenoid). We should have talked about this from the start and I'll ask any moderator to take the side of caution in assuming we have "good mechanics" who are victims to my rash logic. I usually charge $500/hour with a $5000 minimum while consulting $100/hr professionals but wanted to give them my own free advice... When I hire software engineers or programmers, it doesn't matter if they charge $200 an hour and I won't pay it unless they have specific knowledge of the system they're working on and maintain their ability to prove they have a deep proficiency and ability to connect the dots from past experiences to earn that pay. Otherwise, people just find a cheap one with the right understanding of how to think and problem solve and can get the job done. If they feel the need to exaggerate their qualifications and tell me how little I know, then no way... Why is it with some mechanics, it's like the first time every time they look at a car and they expect to get paid like a problem solver who can save time and money while they throw a checklist designed to earn a profit? We have coders like that too, make no mistake, but they don't generally hang out on StackOverflow offering free advice to the online community and they never hijack someones post with emotional baggage.

Lastly, my goal is to summarizing the post for others while filtering some of the pre-requisite tests.

Okay, now JagV8 and Ronn can go back to inflating each others egos while people are literally dropping their jags off at the scrap yard because they couldn't fix their issue with a new battery and or get to the bottom of a PATS 24 or no crank/ no start condition.

 

you are miles off track mate .
have you even plugged SDD software in to the car and scanned it ?
plus if you had the dealer SDD you would also have all the wiring diagrams to follow included .
and you can also see if any SCP or CAN networks are broken and whereabouts .
which is all very relevant and could lead you somewhere .
and you can see if a module has crashed & reprogram modules that may have crashed .

you have already bricked the car . why not listen to the local knowledge & professional advice given here.
and actually try some diagnostic work in stead of going on seemingly ridiculous tangents .
these guys offer sound experience and guidance . for free i will add . but you'r giving up on them it seems .
the S TYPE does have a very unique electrical system and therefore a stringent diagnoses requirement .
all laid out in IDS/SDD for mostly free bar the required laptop and interface .
it includes the need for dealer tools for most things more complex than a light bulb swap .
i believe this un-willingness of yours to see logic and follow steps will cost you in the pocket at this rate .
you need to be very clear that if your 3 knowledgable acquaintances are dead certain thy are referring to the s-type in particular .
because just any old AUDI or Toyota knowledge will not doo here .

 

I'm a great problem solver and build and debug applications with very abstract and complex systems. That's my hobby that turned into a career.

What I see is you telling me I need a special tool from the dealership or else I can't form an educated opinion about how a solenoid ground switching wire is hooked up after looking at the wiring diagram.

Full stop. Learn how that system above works? That's the feedback I'm holding space and think I already know the answer. We tested pin 6/14 and had 600 ohms and did some diagnostic work and will continue to on the solenoid.

I'm listening to local knowledge and professional advice and will continue to do so but at this stage we are not adding value if we leave unanswered questions like what happens when we power the ground wire to a solenoid connected to the PCM without a fuse. If this were a computer program that would be a massive potential bug and there would need to be a time that we need to resolve the potential performance loss. I can't just hook up a computer to talk to my computer and program it... That's my job. If we build around it like it doesn't exist, we lose time and money for being lazy. Programming IDS/SSD into a Windows 7 PC to run diagnostics on the modules is a respectable suggestion but I'm afraid it's overkill and if you want to go textbook, where does it say a module is to blame when you know of the exact short somewhere? Why would we even start there knowing the ECM is between them and possibly signaling false positives and is an easy visual inspection...

If the solenoid ground is open we get one result and if it's closed we get another... Isn't it really just that simple? We could pin the wire with a multimeter and take out the PCM and look at it and put it back 20 times in the same amount of time it took to install SSD and there's a chance it can't do what I'm asking any better than a human.

 

A quick recap from other posts about PATS 24 suggest it's an issue with the computer not talking to the car. In one case it was a loose harness and it showed a different reading than our 600 ohms on the ODBII reader port we probed. That means, the break is likely inside the box and a burnt pin or transistor near the VVT solenoid output preventing the entire relay from working and the parking brake and other modules to show failures. Going into these with SDD or other tools is ignoring the obvious in favor of textbook troubleshooting that is designed to lead you to solutions exactly like it. At the end of the day we still need to rationalize and use our brains and all signs point to taking a look at that ECM. A computer that is shorted, and doesn't want to talk, isn't going to spill it's secretes any better than the error codes and flashing PATS light. Those two indicators should tell the engineer that designed the system the logical failure and where the current breaks, without going to the dealership to have it scanned and then some mechanic without critical thinking skills to get stuck on the same problem that has nothing to do with the car and everything to do with the lack of common sense. I'm under the impression the system is saying that there is improper communication on the back of the short to ground, given we checked every fuse and the important relays... it's possible the ECM is the culprit.

 

No your still off track . even the ECM has a fuse . If it’s powering up .
And not functioning it most probably does need SDD to reprogram it .
do you use an egg beater to debug your own programs ? Doubt it !

(If the solenoid ground is open we get one result and if it's closed we get another... Isn't it really just that simple?)

No you get a scenario not a result. If you want results try diagnosing as the car was designed to be diagnosed.

Your diagnostic thought train is on the wrong train .
i have had can communication failures with my jag .
and without IDS/SDD My car would still be in the same state yours is in .
stop over thinking it .

 

We're getting some idea of how it works but no real specifics on special tools (torx 30 five star), or once the ECM is out, where this fuse lives, or why it would need to be reprogrammed.

You raised a new question. Is it powered up? If the front console powers up with error codes are they the same every time we don't have communication from ECM to CANbus? Wouldn't the computer say it had issues if it could powerup and do so? It sure sounds like PATS 24 and those codes mean no, it's not powering up fine. With 600 ohms it is connected but not powered. This understanding and logic is good if we can confirm with someone experienced that it is the case, it also leads us to opening the ECM and finding this fuse that I don't see on the wiring diagram for 2006 STR.

The fuse you talk about isn't between the ground switching and solenoid and we've been over this a few times and people seem quick to point out irrelevant information if it makes their argument sound good. When something electrical gets a full short to ground generally the first connection fails and it doesn't get a chance to travel through and reach the fuse powering the computer from the other end.

That's why it's important that when you're making a point you leave your ego and emotion out of the equation It feels like I'm rebuking you because of my own ego and make it about who is right but I'm just going to ask you to stop leaving feedback if it's malicious.

It's progress and starting to look like troubleshooting steps someone can repeat and codes we can track. Right now we're just asking for more codes when the ones we have are tossed out without further investigation and no amount of flashing is going to save a burned out transistor that could get us on the road to have a shop scan it later. Even with your best ego trip, you have done very little to prove your experience or persuade me otherwise.

Is it a dealer SSD or home version you can now own? Is the car bricked and if so why are we simply reprogramming it? Bricked ECM's are lost beyond prepare and yet another false or misleading argument to make it a personal debate. If professionals can't be trusted to offer straightforward and honest feedback it does more damage than good and distracts everyone from making meaningful advancements. Yes, a SSD would tell us something new and it's a powerful tool but there's a learning curve and we haven't proven we can think objectively about the codes and resistance test the areas we have.

You use a lot of words like "ridiculous", "un-willingness to see logic" and compare things to "light bulb swaps" if they can't be done by our suggested SSD. There's nothing professional about having poor communication skills and I don't welcome that kind of distraction from anyone even if it is their free advice.

It's good to know I can program my own computer and this does interest me. Especially if it is a fix after a short situation. What happened to your Jag that you found a reprogramming works? Was it shifting bad, module needing tweaked, or routine maintenance, or something very similar to my short?

There's no "wrong train" when approaching a situation with logic. There only exists constructive feedback and sharing of new information. If you're sending cryptic hints or not releasing data to definitively lead to the need for something you suggest and not open to alternatives then you're implying we should not think at all and just trust others to tell us how to do it when they don't know why themselves. This is usually the opposite of how information sharing communities work and I imagine we will still need to fix the ECM once we spend the time learning the SSD. We still have several 5 minute tests to relays and troubleshooting steps using a simple multimeter.

Now we really are just entertaining each other and I could have simply fixed the car by now but I'm waiting on tools. Hopefully this is the last time I need to declare my intention and what I expect from anyone willing to help. There are plenty of people that need free advice and I have no problem waiting for the right kind or seeking it out elsewhere if you feel I'm being intolerant or ungrateful by asking for their reason and logic. Good suggestions that are not fully realized are buried and I told you I wanted to wait on getting Windows 7 or investing time and money in SSD until I understood if the ECM has any visual damage.

 

Now if you guys don't mind and nobody has anything to add, I want to take a look at this PCM/ECM, or do my simple resistance test before we continue.

Is everyone okay with that or does someone want to question my intelligence again?

I found a Reddit group and Facebook group with technical help and I can get a second opinion there but I think I had information worth investigating from day one with the solenoid to ECM test. I can inspect it and send it for testing and repair and then go and buy a computer to run SSD if it is not visibly damaged.

 

I'm still debating whether or not to buy the repair manual and going through the free Jaguar Workshop Manual to see what kind of information I can find form my MY. The $30 book seems very thorough but I did find relevant information up to MY 2005 that is likely similar to 2006 for my issue.
https://workshop-manuals.com/jaguar/...dtc_p1254_set/

I'm not getting a P1254 but this has a mention of a code 24.

As per the PATS System Diagram :
"When a PATS fault is apparent, the instrument cluster will store a DTC and indicate this to the customer by illuminating the LED in the following manner. The LED will be illuminated for 60 seconds"

Now, none of the "Non customer" PATS are P codes but I assume that just means I may have the error without being able to scan the ODBII with my common scanning tool and I may still have them but don't yet understand the correlation between the codes, a $99 dollar Jaguar scanner and the mongoose hooked up the computer. Also, I need to understand if it attaches to the instrument cluster ODBII port or directly to the ECM harness. I don't think it's a CANbus terminating resistor (using a multimeter I get 60 ohms..). If I have a P1254 stored in the ECM and it is the point of failure I may not see the P code part.

http://www.bluejag.co.uk/Jaguar-XT-T...t%20System.pdf
Electrical failures can be caused by problems with the connectors and their pins. Below are a number of points that may aid in investigation. Backed-out Pins Inspection of the connector; look for signs that the pin has backed-out. If a seal is fitted to the pin it may be protruding further out the back of the connector. If a pin has backed-out of the cavity in the connector, there is a possibility that it has been forced out when the connector was mated. Make sure that the pins are in line when the two halves of the connector are mated. Bent Pins Disconnect the two halves of the connector and visually inspect the pins. If a pin is bent over there is a possibility of a short from pin to pin. Pins can easily be bent over when the connector is mated. Check to ensure the pins within the connector are not knocked out of alignment before the two halves of the connector are mated.

Now here's the interesting part. In the first link, it suggests (code 24)
"Situation:
The engine Malfunction Indicator Lamp (MIL) may be illuminated with Diagnostic Trouble Code (DTC) P1254 stored in the Engine control module
(ECM). This may be caused by the throttle limp home spring diagnostic incorrectly diagnosing a fault when there is none present."

Incorrectly diagnosed a problems when there wasn't one present would indicate a ECM reprogram to reset it.

However, if we are considering wether the ECM is even starting we can again look at link 2:
"Engine cranks but will not start If the engine is cranking it means that the ECM is enabled with respect to PATS. If PATS was disabled the ECM would not engage the starter. This could be confirmed by verifying the PATS LED prove-out (illuminated solid for 3 seconds) or by reading Diagnostic Trouble Codes (DTCs) from the instrument cluster and ECM."

This is in line with the logical conclusion that checking the pins and harness first and then perhaps investigating how to open and visually inspect the ECM and whether it would matter as far as dealership flashing and DIY... then of course if there is no damage go through the process of installing IDS/SSD and running further diagnostics, if it's possible for ECM communication.

And more importantly, this is why we are doing it and we can discuss possible damage, tools, shortcuts etc. If anyone has knowledge with the MY.

I also wonder if this is the same code 24 as the PATS 24 blinking non customer code. Is there a list of the codes and comparison to how they relate from service manual to the PATS?

I'm close to feeling confident enough to tear into the next step.