And once it has done that and said it's OK to start could it change its mind and say whoa boys stop that engine?

 

Yes, I would imagine so. But I wouldn't think it was because there was some kind of way that the engine was running, that it didn't like, that would reverse that OK command.

Honestly, there have been so many back and forths in chasing this issue that I am unsure what has been said, tried, probed and attempted, and what has not BUT, I would think that (for a simple lack of power) one of the major components (like KTM, BPM, ECU or MIC) is shutting down mid steam, due to a bad earth, a bad relay or a faulty/dirty connection somewhere. But that's just me.

Has the OP opened or tested the in door fuse box MAIN relays for resistance, corrosion, malfunction? I mean, they are right there. Easy to get at.

 

I agree a clear summery of what's been suggested and tested would be very helpful. I see this as a logic problem and the killer question is just what can shut the engine down after two seconds? A bad earth for example would be unlikely to be a consistent 2 seconds - but as ever what do I know? Not as much as you guys that's for sure

 

Not knowing, is perfectly ok in forums,,, and apparently at fancy auto garages as well, lol... Them folks, omg

Not unlikely. And it's not consistent. Sometime the OPs car runs like a champ...

I just finished rigging up electric fans, PWM, and sensors for it, in my XJS. In testing, EMI from the 7000 pulses per ****** earthing of the 2 fans OCCASIONALLY would stop the engine flat. Dead. Confused the crank position sensor that lives 10inches away... Then, a few seconds later it would start right up. Then, on my XKR, a dead spot in the ignition switch most often would not allow the car to start (final key turn) except 1 out of 50 key turns, some days it would be better, some days worse and it got gradually worse to ZERO times (I started looking in the COMPLETE WRONG direction - for months!). I had a set up where I would turn the key to the run position,,, had a hand held trigger in the front seat, pull the trigger and hit the road. Then I found the issue.

Simple old fashioned mechanical (easy to fix) electrical failures on these cars, I think, are going to be more and more common. A 25 year old relay that has a carbon spot growing on it for example. Figuring out what they are, cornering them, without spending a million hours or a million bucks, well at least me, is what I'm hoping for. God willing.

 

As I say I'm learning and I look forward to the resolution of this problem.

 

Daro. Are you saying you get a warning - of sorts - that comes with revs climbing - then stall?

Or, are you saying that when you start the car, in the 2 seconds that it runs, then stalls, the initial revs (at start) are 1100/1200, then it shuts down? If this is the case, 1200, 1300 AT start up is not that unusual before the idle starts to settle, coming down below 1200rpms then eventually settling down to 680, 670, 660 and so...

Brotha. We need you to get a little BETTER at describing what's happening and what you are experiencing. Also, just speaking for me, to try some things and give a clear and detailed set of descriptions about what you are doing, have done and would like to do... Especially when the problem is happening.

 

I think it's worth clarifying what the different 'security' areas do.

The immobiliser is the KTM (definitely in the dash area), ECM, IC and BPM acting in concert to prevent vehicle theft by disabling the motor start other than when presented with the correctly-mated ignition key(s).
The car can be started, so IMO that almost certainly rules out an issue here.

The security & locking module is tasked primarily with the car's perimeter security: doors, hood/trunk/bonnet/boot and top/hood, together with vehicle access via the remote fobs. An issue here won't impact the car starting or running.

The inertia switch is for crash safety protection, and will flag the ECM when it trips so that fuel can be shut off and the doors unlocked. Apparently, the motor can be cranked in this state, but fuel supply is inhibited.


It's important to establish what happens after the 2 second delay. Given that compression won't disappear on all 8 suddenly, we're left with 1) spark or 2) fuel, via pump & injectors.


Do you still have the original ECM? The symptoms seem to be different since it was replaced, so it may shed some light if it's substituted back. I've read through the VIDs documentation provided by motorcarman and it does not specifically warn against doing this.

 

I can start the car normally and the revs climb quickly to 1100 rpm. and then shuts down no stumbling like fuel shortage just a shut down after about 2 seconds. There are no error codes generated by this action. I can repeat this start run shut down sequence over and over again
I have put the old ECM back in but now I get no response from it.
I have a British Diagnostics Mongoose and an ICarSoft 930 for Jaguar/Land Rover. Both of them are indicating that they cannot read the presence of the KTM.
I have sent numerous emails as well as using their web contact page asking for help as I cannot get any response from their software when I hit the service functions button. I am not very pleased with their after sales service.
I have checked every fuse and relay on the car and have come to the conclusion that they must be related to this KTM module. I cannot however seem to make any changes to it with the iCarSoft scanner and their instruction manual is very thin and not helpful in actually changing anything.

 

Notice on the readout from the Jaguar SSD diagnostic that the KTM, Key Transponder Module has a question mark. When I go to Service Functions, I get no response. It acts like it is trying to connect to a Jaguar Website. This is what I have asked British Diagnostics about several different ways, and I get no response. Early cars pre-2003 seem to indicate that the wrong key would not allow the starter to even turn over, nut a JTIS bulletin sent to me says that after 2003 the wrong key shuts down the ignition, fuel pump and injectors, which seem like the way the car is stopping.

Screen shot of Mongoose diagnostic

 

Remove the key transponder module and post a picture of it. Please include the serial numbers. You can find one for 50-60 bucks and have it reprogrammed...

I'm not sure what you mean when you say youve reinstalled the ECU and it's unresponsive or didn't change anything. Does the car do the same things with the old ECU, or does it do nothing at all!?

 

With the old ECU the car is unresponsive.

 

"With the old ECU the car is unresponsive."

Darn! I was hoping it'd start and continue running; even rough would tell us something.
Interesting that the repair outfit could extract the data but return a bricked ECM.

 

You can pick up a dirt cheap immobilizer ring tester and verify it broadcasts a signal out for a key.

For my XKR problem, I sprung less than $10 and picked up one up and was very glad I did. It verified the immobilizer was working on the '06 XKR and the '97 XK8 didn't have an immobilizer. The key man lied to me and charged for RFID chips and programming spare keys on the '97 and he did not insert chips in, nor program any '06 keys.

If you hit up Amazon for the "Joofn Car Key Test Coil Auto Induction Chip Signal Detector Auto Immobiliser" you can score the last one and have it in a couple of days. Watch out, though, if you order a different one, you might not see it for weeks. There's some on ebay, mostly from China, but there are US sellers .

The fact that it turns over and fires is a strong indication the KTM works and has a matching key code that matches one in its memory, so it sends the "key valid" signal to the BPM which sends s 3 byte packet to the instrument cluster for it to swallow and then set the flag for key valid, that the ECM will look for when the key is turned and permit fuel/spark/starter to roll over and run.

 

I bet if you look in the old ECU you will find the capacitors have been removed and the board is damaged ....they could not repair it so just sent it back...If you are good enough with a soldering iron ,some bits of wire and a brain you can mend it .

 

FRom day one... Tied to start the car, stumbled and coughed confused. Tried again, same thing. Produced the codes above. Car was looking for information it could not find in right running from stores information (as the ECU does)...

Everything I have looked at in relationship to these codes talks about checking for faulty connections that could create a low and improper voltage situation to major modules (ECU/PCU) or instruments that hold and provide this data to the the ECU/PCU...

 

With all of the good suggestions that have been offered up, I am not sure what has been tried, not tried by the OP, and I cannot go back and read 6+ pages 100+ entries.

At this point LOTS of different investigative suggestions, tests, probes, readings - or whatever ya wanna call them - should have been tried attempting to CORNER this issue... Then detailed results reported and offered by the OP, then additional help from the group here... Good reports and descriptions go a long long way. Lol, me, I love pictures.

What procedures were used to test your fuses and relays? Were known good relays (from rear window defroster or horn for instance) swapped with relays that run the ECU and BCM? Were the fuses for the KTM and other important modules like the ECU swapped with new just be sure? What main wiring looms and multipin connectors were inspected? What pages from the electrical diagrams are being used to chase the locations of things, issues or possibles? Do you have a DMM? A test light? Has the forum been a source USED by the OP to determine where the KTM is before going to look for it?

Work with us here, Brother Daro! Work with us here!

 

The is from the engine management diagrams 4.1 from the ED... All this (and a lil more) needs to be backtracked and checked and reported back on so folks can help and offer suggestions.

It's pretty clear how improper power here might cause a problem, or 50...

 

I was also hoping that might have given a clue

I take it that means that the car won't crank with the old ECM. It may well be that the immobiliser is kicking in with that scenario. I missed this when I read through the VIDS stuff:

"...the next stage is to transfer the ECM’s unique Passive Anti Theft System Identification (PATS ID) to the other control modules on the vehicle that require it. The control modules that store the PATS ID vary from vehicle to vehicle."

..so it may be that the old ECM would need to go through the config process before the car will start again.

It would be useful to know what happens at the point of stall - no spark? no fuel? Both?

 

Deleted

 

"It would be useful to know what happens at the point of stall - no spark? no fuel? Both?"

Yes, a voltmeter or simple continuity light tapped into injector and coil may answer that question. The external fuel pump was pretty slick and answered the question of fuel pressure.

I make up probes and jumper wires with straight pins so I can slip into a connection without permanent damage.

Yesterday, I solved wife's PT Cruiser's two O2 sensor heater errors by poking around with Volt/OhmMeter and finally tracked down a bad harness connector. I jumpered both O2 sensor heaters to external grounds and resolved that nagging CEL that created temporary bucking and stalling shortly after startup as the PCM couldn't read cold O2 sensors. Would've saved a lot of time if I could've found wiring diagrams online.

This afternoon, I poked &, prodded both VVT solenoids for the umteenth time, even tapped in an extra ground wire to bank 2 with the P1396 error on our '99 XK8. Both banks have same exact voltage, beautiful PWM waveforms, resistance to ground, but bank 2 throws the code. I might not have discovered the problems, but at least I can see what's going on. (I'd switched solenoids and doublechecked short chain tensioners long ago, so save those suggestions)..