Looks like it's working now.


This is how it was tapped to the wire bundle

Here it is untapped from the bundle

 

There are several unused connectors in most Jaguars that were for temporary use prior to vehicle delivery to the customer, or for connecting optional equipment for upgrades or market-specific devices. Just tape the connector back to the harness when you've dried everything out.

 

Will do Don.

 

It appears that the cover to the TCM/ECM compartment has some thin foam tape that, presumably, is supposed to keep out water. On mine that foam appears to be compressed to the point of uselessness. I'm going to go pick up some similar foam tape and see if that might help in future rain episodes. Also there were 2 foam cubes laying in the bottom of the compartment in the area where the water was accumulating. I'm not sure if they were initially glued to a component or just sitting there for support. I've taken them out and set them in the sun to dry out. Anyone know what, if anything, they're supposed to be attached to? There are similar foam pads attached to the cover that hold down the TCM when the top is installed.






These are the foam blocks on the cover that hold the TCM in place.

 

In looking around near the compartment I see what appears to be another drain, similar to the cowling drains that run along the outside wall of the compartment. However, I can not find where this drain comes from. It appears to drain out somewhere along the firewall. Anyone have any ideas? By the way, I was able to fish a wire through both of those cowling drains and neither is blocked.

This photo isn't the best but you get the general idea. I'll try and get a better photo when I get back from shopping.

 

OK, everything dried out, the sun actually came out, so I plugged everything back in, reconnected the battery (reset the windows) and started it up and I STILL get the same "GEARBOX FAULT" and "RESTRICTED PERFORMANCE" messages. I plugged in my OBD2 and got the following codes:
P1643 CAN link engine control unit/transmission control unit circuit/ network malfunction
P1748 Pressure regulator 5 malfunction (this is something I've never gotten before)
P1260 Security input/Theft detected, vehicle immobilized
U2500 CAN bus error

Any suggestions???????

 

According to google/bing the P1748 message indicates that the Electronic Pressure Control solenoid may be the issue. I've been trying to find the location of this item but haven't found any help. Any guidance would be appreciated. I've read some threads on here indicating that I can just use the OBD2 to clear the codes and then just drive the car. I'd rather find out what is wrong.

 

Did you disconnect the ECM and TCM and inspect their electrical connectors for corrosion? When there is water in the compartment, the increased humidity can promote corrosion on the electrical connector pins and terminals.

Since you haven't had the P1748 before, I wouldn't worry too much yet. There's a good chance it was triggered by disturbing the TCM, but it does suggest that resistance in the TCM-to-transmission circuits could be a problem. The pressure regulator is an electro-magnetic solenoid mounted in the valve body inside the transmission fluid pan. A common cause of this family of DTC is an open circuit or increased resistance in the wiring between the transmission internal electrical harness and the TCM, sometimes due to corrosion on the TCM connector pins, or oil contamination of the pins in the transmission electrical connector. Here's the definition from the X308 Workshop Manual (for some reason the X100 WM doesn't provide this info):



Can you clear any of the codes? And if so, do they recur when you re-start the engine?

I can't remember - did we discuss measuring the resistance on the CAN bus? Your CAN codes could potentially cause the gearbox fault and restricted performance.

 

Don,

Yes, I took every connector off the ECM and TCM and didn't see any corrosion. The pins are kind of small so it's difficult to tell but nothing obvious. I sprayed every thing with CRC and let them all dry.

I plugged the OBD2 back in and cleared the codes and when I restarted it the 1748 code was gone, just the 1643 and the ever present theft message, which, at this point, I'd be perfectly happy if someone stole this POS.

No, we've never talked about measuring resistance on the CAN bus. How would this be done?

Joe

 

The two foam 'cubes' are glued to the ECM to keep it in place when the lid is ON.
Look for evidence of glue marks on the ECM.

 

Hey Motorcarman,

Thanks for the info. I didn't see any marks on the ECM. At this point I just put it and the TCM back in place and am trying to figure out what the hell is wrong with this thing. If I should ever get it to resemble a running automobile I'll see if I can fix the little things. However, I'm beginning to think I'm just going to use it as lawn art again. It took 6 months to get the CAT monitor to clear, I'm guessing this is going to be a year.

 

I can't find U2500 listed as a valid DTC for 2001 (or later 4.2L cars) in any of my references. Are you certain that is the correct code? It could be that your scan tool is trying to make sense of data it doesn't recognize. If anyone has a Jaguar document from the X100/X308 era that defines U2500 please let us know.

Regarding the others, here are the definitions and possible causes:





I think that now that we know your EMS compartment contained water, it would be prudent to clean the grounds referenced by the ECM which are there in the box or near it. I seem to recall that the ground referenced by the TCM is in the left hand compartment, but I may be wrong. Check the Electrical Guide to confirm.

To do a couple of basic checks on the CAN, with the ignition OFF you can measure the resistance between pins 6 (CAN high (+) Yellow wire) and 14 (CAN low (-) Green wire) of the Data Link Connector. A good reading is about 60 ohms. If the resistance is much lower than 60 ohms, there is a short in the network. If the reading is much higher than 60 ohms, there is high resistance in the network. Now set your meter to voltage and, with the ignition ON, measure the voltage from pin 6 and ground. It should be about 2.7 volts. Then measure the voltage from pin 14 to ground. it should be approximately 2.5 volts. Any significant difference indicates a problem with the network.

For additional diagnostic steps, see the attached document.

Cheers,

Don

 

 

Does your scan tool indicate which module is reporting the U2500?

Did you note any letter codes with the PECUS warning lamp? It could be that the module reporting U2500 is also triggering the PECUS warning.

I just checked the 2010 Jaguar XF and 2012 X351 XJ DTC Summaries and no U2500 is listed for those years either.

 

The 2500 was the code from the TCM.

I don’t recall any other information on the PECUS message.

we’re babysitting 3 of the grandkids tonight so I’ll have to check tomorrow on that.

 

I'm attaching more reference materials. After cleaning the ECM and TCM grounds, the next step might be to check and clean the electrical connector on the rear of the transmission. Oil contamination is a common problem.

Have fun with the grandkids!

 

please excuse my ignorance but where are the TCM and ECM grounds? I’ve ordered new ground straps for the frame/trans ground. They’ll be here Sunday.

 

See post #52. That's as close as I can remember. Hopefully someone else will chime in who has cleaned them more recently.

 

Hi Don,

Just got home from babysitting and read that earlier post. Maybe I’m getting dumber as I age but I’m still lost on the ECM and TCM grounds. Or maybe I’m too tired. I’ll post some pictures and see if I can figure out where the grounds are that you’re talking about.

I’ll do the pin checks on the OBD2 plug tomorrow. I’m pretty sure I did those tests before and got the correct readings but I’ll check them again tomorrow.

Joe

 

Is the ground under the round black cap?