The one thing I've always been able to count on with this 2001 XKR is that it would crank. Now, I've got a crank/no start condition. I can smell fuel getting to the engine. I suspect something to do with immobilizer. Codes from the iCarSoft:

Multiple systems: "Fault in communication with vehicle ECU."
U2012: Communication bus error - non SCP.
B1595 - Ignition Switch - illegal input code
U1041 SCP vehicle speed signal - invalid or missing data
B24BD - Diagnostic trouble code invalid
U1135 - Ignition status not obtained
U2500 - CAN bus error

I have been getting intermittent body control module errors and TCM to ECU errors as well. Yes, the battery is charged and excellent. At least it's in the garage and not in the driveway.

 

It seems likeyou have a little to chew on. Is there anything you have done lately that could have upset the car? Il guess its abbout th see if there are a common member/box that could be the root problem.. perhaps security module? That is one of the important boxes that is not very well enviromentally protected.. its just a cirquitboard with two plastic pieces snapped togeather around it, corrosion on the tiny tracers is not uncommon.

When i bought my 2003 XK it only took a few days before it started to have issues with the dreaded CAN bus, no communication between ECM and TCM. I checked and cleaned out several electrical connectors and some of them looked as there was oil in them, most likely degraded some kind of electrical "waterproofing gel".

In the end it was the last plug i cleaned that got rid of my problems; the plug on the gearbox.

The XK series 100 is cramped with all sorts of electronics.. witch also get old over time.. every now and then we are going to have to face issues..

/E

 

Can you open and close the passenger side window with the driver's side controls? Likewise lock/unlock the passenger door with the driver's door handle? That's a simple way to test if the SCP is working - those error messages seem to suggest it isn't. You can't really test the SCP network with a multimeter, but you can do a simple check on the CAN bus - its should read 60 ohms across it (test at the OBD port) with the ignition off.

 

If what dibbit has suggested checks out, I'd be looking at i) fuelling and ii) ignition. If the car will crank it's unlikely to be an immobilisation issue & I'd expect a P1260 to have been thrown.

Do you have pressure at the schrader valve on the fuel rail (cover it with a rag and depress the centre pin)?

Check F5 (10A) in the Engine Management fusebox and F5 (10A) in the Engine Compartment fusebox. I'm not sure what accessibility is like on the S/C, but if you can get to the injectors, check for B+ on any of the injector Brown/Red wires. A test bulb is best for this rather than multimeter.

Have you checked for spark?
Check F14 and F18 (both10A) in the Engine Management fusebox.

Most of the codes you've reported are frequent visitors and may well be historic/ghosts. None of them are shown for our cars until the 4.2L OBD lists- although perhaps the earlier documentation is incomplete?

If you don't have an emissions test on the horizon, I'd just clear them.

 

After seeing some threads on this subject recently, the same thing happened to me on the road a few days ago. Taking the fwy exit to our daughter's house near Davis, CA on Monday, the engine died at the stop sign. Coughed and sputtered enough to drive and push it across the intersection to the shoulder. Long story short, towing it 135 miles back home was rejected and took it to a shop in Davis that confirmed my diagnosis of a failed fuel pump. It is still there, so confirmation of the cure is not until next week, but they said that it would only be one pump, while other sources that I have seen online are saying two pumps in parallel. (2002 XKR, 4.0L) They will obviously determine the truth when they open it up.

My daughter suggested that I ask ChatGPT about it. It also said failed fuel pump, but it seemed to think that the XKR has a saddle tank with a transfer pump. One more reason to distrust computers.

At least the Jag pumps are more reliable than the ones that BMC used in the 1969 Austin America that my wife had back then. 12K miles was the lifetime of each one.

 

Still troubleshooting. Where is the location of the schrader valve? I have a strong fuel smell when cranking so I suspect fuel is at least getting somewhere. All fuses seem to be intact. Could a bad BPM cause a crank/no-start? The trouble spot on this car has always been the connection to the transmission, which is inaccessible in its current location in my garage).

 

At the end of the fuel rail, hard to see with the supercharger intercooler parts in the way

 

If you're smelling fuel, I'd pull a sparkplug and see if they are fouled. And it could just be borewash.

 

doing so more diags. It WILL pop off for about a second with a shot of starting fluid into the throttle body. So we have spark. I'm suspecting fuel pump, fuel pump relay (which I have swapped so likely out of the picture), or clogged fuel filter. This is an XKR so there are two fuel pumps, right? At the schrader valve I get a little spurt when I hit it the center pin... I can't do that while cranking as I'm flying solo right now. I don't suspect borewash since this engine was pulling fine before the odd starting issue.

 

OK so there's life in there somewhere

You don't strictly need to be cranking check this. The pump runs for about 2 seconds at ignition on to prime the system, then shuts off until the engine fires.

I would do a fuel pressure test at the schrader - you should see around 40 psi.

For the sake of good order, change the fuel filter anyway. It's cheap and not too difficult to get at.

 

I've got adequate fuel pressure at the schrader valve. Everything here is pointing to the injectors not getting signal to fire. I suspect a bad ECU. I have a part and year-match spare ECU. Does anyone have a programming/cloning service?

 

Hi 2500,

Have you tested to see if bladerunner919's suggestion of borewash may be the issue? To do so, remove all the spark plugs, blow out each cylinder with compressed air to disperse as much residual fuel as possible, inject about 5 cc of motor oil into each cylinder, crank the engine a few rotations to distribute the oil in the cylinders, clean any oil from the spark plug bore hole threads, reinstall the plugs and coils, and test start the engine.

Another possibility that you could be dealing with is that if the voltage at the ECM falls much below 11 volts while cranking, the ECM will not trigger the ignition to fire, and may also not ground the fuel injectors to pulse them open. Try measuring the voltage across the battery terminals while cranking the engine (an analog voltmeter is best for this - digital meters don't respond quickly enough). It is possible that your battery is fully charged, but no longer has its original Cranking Amps capacity. Some auto parts stores have battery analyzers that can measure the capacity of your battery.

If the voltage is sagging and the battery really is healthy, I would suggest cleaning the various battery and ground connections throughout the car, beginning with the engine ground strap (clean both ends as well as the points they connect to at the body and engine), the battery negative cable connection to the body, all the connections and fuse blades in the High Power Protection Module in the trunk/boot, the battery positive connection at the false bulkhead under the hood/bonnet, and the battery connections at the fuseboxes under the hood. I personally would perform this service before considering swapping in a different ECM.

Cheers,

Don

 

If you have a spare ECU then no reason not to swap it to eliminate the old one, but you will have to do the immobiliser setup on it, for which you need Jaguar's IDS/WDS software. I think some scanners also have this facility. This may be trickier than you think on a non-working car.

Having said that, the fault is still more likely to be a failed sensor, or broken wire, or bad connection somewhere or any of the things that Don B listed above. Personally I would eliminate those problems before trying to setup an unknown ECU.

 

Since you seem to get fuel, (fuel smell) perhaps the crank sensor is shot.. no crank info --> no ignition.

/E

 

It's interesting. I just popped the ECU in the other day, and it cranked/no start. I didn't expect it to crank with a foreign ECU.

 

In theory, it's supposed to require an immo setup, but some seem to drop lucky and it just works. As there's no apparent change, I'd recommend that you refit the original ECM so you're not introducing any more variables.

So, you can get the motor to try by squirting starter fluid into the intake, which bypasses the injectors. Can you access any of the injector connectors on the S/C engine without taking things apart?

 

I may be able to. When I get time, I plan on seeing if the injectors are firing or getting power. My theory is that if it's a bad ground, I may be able to wire a secondary ground to the injector rail UNLESS it's a bad ground before the fuse. Come to think of it I could probably just test the hot at the fuse and the ground at the rail.....

 

Thanks Don. I can get it to run for about 2 seconds on starting fluid. Would this eliminate the possibility of borewash?

 

do you have spark
do you have injector pulse
do you have compression

when you confirm these 3 i will help you out. last bit of info i’ll give you is a mismatched ECM still cranks because the the KTM has 2 different immobilization channels

 

You can confirm the injectors are getting power by checking for B+ on any* of the injector Brown/Red wires (ignition on-position ii). A test bulb is best for this rather than a multimeter.

If not, check F5 (10A) and the injector relay (both in the Engine Management fusebox), also F5 (10A) in the Engine Compartment fusebox.

Checking if the injector is firing is a little harder.
To fire an injector, the ECM supplies a ground signal, but only for a very brief period (~3 milliseconds) in each cycle. You can use a 'noid' lamp to detect this:
https://troubleshootmyvehicle.com/gm...oid-light-test

Alternatively, if you have a multimeter with a 'Hz' setting, you might get a reading across the connector pins while the motor is cranking.


* NB the EG shows both wires connected to the injector in position B4 (cylinder #8) carry the same two colours.