So a couple weeks ago everything was just fine with this car. No lights, no warnings, now codes. I had it backed into the driveway so I could put the trickle charger on it and there is sat. I ended up in the hospital emergency room for some "tests" and wound up having my gallbladder removed. Fortunately it was arthroscopic surgery so my surgeon tells me my career with Chipendales is still a possibility. I'm been healing up for the last couple weeks and went out today to run to the post office. I unplugged the charger, got in, put the key in the ignition and started it up. BAM! "GEARBOX FAULT" and "RESTRICTED PERFORMANCE". I limped around the corner to the post office and back home. Oh yeah, I also got something called PECOS showing up on the dash message window. Now it did rain for the last few days here in Sunny Southern California but I didn't know these cars were allergic to water. When I got strange codes before, like ASC NOT AVAILABLE, LOW BRAKE FLUID, etc. they were because of a low battery. Once the car started I could shut it off and restart and the codes would go away. Not this time. With the charger plugged in I'm getting a full 14 volts +. So that isn't it.

Anyone out there have any idea why, after a little rain, the car would do this, go into limp mode and just sit there? This is beyond a doubt the WORST car I have ever owned, and I've owned some real POS over the years.

 

Joe, sorry you are having difficulty after a rain, but since you don't normally have an issue with rain you wouldn't know to check the drains at the firewall. Open the bonnet and look at the shelf behind the latch. You should see a drain hole with a screen over it. Look on the other side of that hole after taking the cover off and there is a funnel hooked to the tab, and it hangs down. Sometimes they rattle loose or they get stopped up. When this happens all the electronics in those enclosed area get flooded with water and cause lots of trouble. A wire can clear the drain after you take out the funnel to clean it.
Open it up and take all the covers off and give it a good chance to dry out or use a handheld hair dryer.

 

Hi Wayne,

Please don't take this the wrong way but WTF!!!!!! Are you telling me that these cars were not meant to be outside in the rain? I'll go out there and check in the area recommended and see what I can see. Is this like a normal thing for jaguars, if they are left out in the rain you can't drive them unless you clear out the water drains? Perhaps, I don't know, if those thing have any chance of leaking, don't put electronic components in there!!!!! Must be a real joy to have one of those new electric jags. Get in it and get your butt fried!

 

Joe, admittedly not a great design or should we call it an afterthought. You must have never owned a MGB either, they had a duck bill rubber at the drain for outside air that would clog up and throw whole design of the weight of water opening the exit to drain, so it went right into the heater and out the duct work for the dash and floor and into the floor. Rusted many away.
Good luck.

 

Wayne,
Only other British car I've owned was a '62 Austin Healey 3000 MkII. I took it down to the frame and had the engine rebuilt and put it all back together. It go stolen. Ah well. Anyway, I opened up those 2 compartments in the engine compartment on the port and starboard sides. Both looked to be dry as a bone. The port side contains the power brake system and the other the TCM and ECM. Neither showed any signs of water.



Is this something that will eventually dry out? Do I need to pull it in the garage and get my leaf blower out and go over the whole engine compartment with it?

 

Hi Joe,

I'm glad to hear you are feeling better after the emergency gall bladder surgery. No fun!

In addition to Wayne's good suspicion of water ingress, another possibility regarding the GEARBOX FAULT and RESTRICTED PERFORMANCE warnings could be low voltage while cranking.

You mention that with the charger plugged in you are getting a full 14 volts. That is not a measure of the battery state of charge or state of health. I suspect that is the voltage the charger is supplying to the battery. A healthy, fully-charged battery will measure about 12.6 volts with no charger connected and without the engine running, and it should be able to supply its full rated Cold Cranking Amps. With the engine running, you should measure at least 1 volt higher, or 13.6 volts or more. If the voltage while cranking the starter sags much below 11 volts, various spurious diagnostic trouble codes may be triggered.

The PECUS warning suggests one or more of the control modules was not recognized at start-up, another symptom of low voltage. PECUS stands for Programming Electronic Control Unit. If the PECUS warning recurs, note the additional letter code or codes and see the attached TSB for an explanation.

Perhaps your trickle charger did not keep the battery fully charged? Could it have been accidentally unplugged or disconnected from the battery?

Many auto parts stores can test your battery state of health to see if it is still capable of providing its full rated current.

Cheers,

Don

 

Good news Joe.
Did you see the little funnel and the hook it's attached too?
I can see it in the picture but it's not something that will jump out at you. The little square part in the corner of the one with the brake on the left downside. Pull up the plastic that is hooked on the tab and make sure the funnel is clear of junk, if so, run a wire down in the tube that goes out of the car.
There is one on each side, so glad you didn't have a puddle waiting on you.

 

Hi Don,

As best I can tell the charger is working fine. The red light comes on when I plug it in and goes to green after charging. I'll throw a multimeter on it later today and check to be sure but I don't think the battery is the problem.

 

Wayne,

I'm guessing you're talking about these tabs that appear to be connected to the little tubes that seem to run from those holes at the bottom of the cowling into the 2 compartments in the engine compartments.


Port Side 1 Port Side 2



Starboard Side 1 Starboard Side 2

I'll have to find a solid wire to fish down the hole in the cowling to see if there are any clogs. I put a light down into the compartments and don't see any signs of water being trapped in there but who knows at this point. What I am wondering was who the electrical genius was at Jaguar at the time this was done. Of all the places that they could have put the drain for that water why would anyone with the least bit of knowledge of electricity put them in the one place where they would come in contact with not only electrical wiring, but the 2 most important computer modules in the whole car, the ECM and the TCM!!!! I mean this had to be a joke on all Jaguar buyers. "Let's let the water drain into the car's most important electrical component so that we can sell more service calls and cars". What complete idiots. (or crafty *******s).

Joe

 

Cranking Amps/Cold Cranking Amps capacity is just as important as state of charge, so it still may be worth having the battery tested on a good analyzer.

Corrosion on various electrical connections between the battery, starter, ECM, TCM, etc. can cause a deep voltage sag while cranking even with a very healthy battery.

For those drains, I use heavy string trimmer line because it is less likely to poke through any soft rubber than metal wire.

 

Joe, it looks like that may not be the issue, sorry about that, but just good to be aware of.
As for the design, yes it sure didn't need to be there and so much room in the trunk, just the cost of longer wires, I guess.
Have the battery load tested, if you get a chance, when starting it pulls a lot of AMP's away from other sensors that give codes.

 

Hey Don,
I'll see if I can run over to one of the auto stores and have them test it.
I'm not sure if I have any weed wacker cable but I think I may have some other nylon type stuff around.

Wayne,
That's the problem I was having when I first bought the car. The battery that was in it was low and I was always getting those messages on the dash screen. Once I installed the new battery they went away, for the most part. Every so often, after either a cold evening or if I hadn't driven the car in a while, they'd pop up again on start up but if I shut the car off and restarted they'd go away. That's why I started using the trickle charger.

Joe

 

Aha! Now we know the rest of the story!

Since we now learn that there was a history of spurious codes that were mostly resolved by a new battery, the next suspects would be the electrical and ground connections between the battery in the trunk/boot and the ECM, TCM, starter, etc. in the engine bay. The things I always address first are:

1. Remove and clean both ends of the engine ground strap. It is subject to contamination from oil and corrosion. Clean away any oily sludge and inspect for corrosion that may have migrated under the eylet terminal crimps. Clean the eyelet terminals with a small brass-bristle brush (never sandpaper - the scratches promote future corrosion) and zero-residule electronic contact cleaner (CRC makes a good one available at most auto parts stores in the U.S.). Also clean the points on the body and engine/bellhousing where the cable connects.

2. With the battery disconnected, disassemble, clean and re-secure the false bulkhead connector on the forward edge of the plastic Engine Management housing at the right side of the firewall in the engine bay.

3. Remove the battery, detach and clean the battery ground cable connection to the body. Then remove the plastic cover from the High Power Protection Module (HPPM), take photos of how the fuses and cables are connected, then disassemble, clean all the fuse blades, threaded studs, eyelet terminals, washers and nuts, flush with electronic cleaner, allow to dry, then reassemble, taking great care to return all wires to their original positions. The nuts on the threaded studs don't need to be overly tight - just good and snug.

It doesn't take much corrosion to add considerable resistance to these critical circuits, even corrosion that is difficult to see with the naked eye. And all added resistance is cumulative.

Often, performing these maintenance tasks will make a noticeable difference in starter performance and will reduce the voltage sag while cranking

There are additional important connections, such as all the power connections to the fuse boxes, the ground points referenced by the ECM and TCM, the connections to the alternator, etc. But usually the connections listed above are the most vulnerable.

I am attaching the wiring diagrams that show the locations of the power and ground connections.

Cheers,

Don

 

Morning Don,

Thank you for all the info. I guess I'll be getting under the car, again, to get to the ground wires on the engine. I'll check the battery and other connections when I get to the garage. Once again it becomes a project car, not a driving car. Oh well.

Joe

 

I think of it this way: these are just basic regular maintenance items on any 24-year-old luxury performance vehicle.

 

Don,


1. Remove and clean both ends of the engine ground strap. It is subject to contamination from oil and corrosion. Clean away any oily sludge and inspect for corrosion that may have migrated under the eylet terminal crimps. Clean the eyelet terminals with a small brass-bristle brush (never sandpaper - the scratches promote future corrosion) and zero-residule electronic contact cleaner (CRC makes a good one available at most auto parts stores in the U.S.). Also clean the points on the body and engine/bell housing where the cable connects.

Having been under the car before I recall that the bolt on the transmission that holds the ground strap is very close to the Catalytic converter. I don't think I can get to it. However, I've seen several videos where owners have attached new ground straps using other bolts. I think I'll give that a try. I can buy a bunch of ground straps for $15. Just a matter of finding another bolt on the engine and frame and cleaning the area around them.

2. With the battery disconnected, disassemble, clean and re-secure the false bulkhead connector on the forward edge of the plastic Engine Management housing at the right side of the firewall in the engine bay.

Is this the false bulkhead connector?




This is the compartment on the right side of the engine compartment. Is the cable with the yellow cover the false bulkhead connector?

If not where else should I be looking?

3. Remove the battery, detach and clean the battery ground cable connection to the body. Then remove the plastic cover from the High Power Protection Module (HPPM), take photos of how the fuses and cables are connected, then disassemble, clean all the fuse blades, threaded studs, eyelet terminals, washers and nuts, flush with electronic cleaner, allow to dry, then reassemble, taking great care to return all wires to their original positions. The nuts on the threaded studs don't need to be overly tight - just good and snug.

Here's the battery. The ground cable connections to the battery and the vehicle look very clean. I cleaned them when I put the new battery in a few months ago.


Overall Battery Positive Terminal

Ground Cable to Body Ground Terminal



Is the HPPM the box just next to it? Are you saying I need to take that whole box apart and clean all the connections, wires, fuses and terminals?



HPPM ?


Joe

 

Hi Joe,

The High Power Protection Module is forward and a little left of the battery, behind the spare tire. Here's a photo of me pointing to its location. If my trunk wasn't full of tools and cleaning supplies right now, I would have removed the floor panel to take a better photo. For a better view, see pdf page 11 of the attached document by our member avt007 (Rob). It was written for the X308 but most of it is directly applicable to the X100.




Regarding the False Bulkhead Connector, sorry if my description was confusing. in my mind's eye I was seeing the X308 connector. On your X100, the connector is down on the inner side of the Engine Management enclosure at the right end of the firewall. Here I'm pointing to it:




Here's a poor photo showing that the connector is down below the A/C refrigerant pipe. I've added an arrow since the black rubber cap is difficult to see. For access, remove your plastic air intake pipe.




Regarding the battery negative cable body connection, it looks great, but the important contact surfaces are hidden. You cannot tell its true condition without disassembling it, and while you have it apart, clean the eyelet terminal, threaded stud, washer(s) and nut and reassemble. Likewise, the battery cable terminals and posts can look clean but have corrosion on the contact surfaces.

Yes, adding a second ground strap is a great idea and I've done it several times when the bolt at the starter or bellhousing was difficult to access.

Cheers,

Don

 

I guess I'll be in the garage tomorrow with my fresh can of CRC and wrenches. Thanks for all the info.

 

Took the spare out of the car and this is what is in there. I'm guessing the little black box is the HPPM. There appears to be some water on the floor just under the box. I've checked the weatherproofing around the trunk and it all appears to be intact. Is there any other place this water might have come from?




I'll get the cover off and take more photos and dry everything out. Same with the battery terminals and connections. Then I'll head to the engine compartment and see what I can find.

Joe

 

Got out my handy dandy 10 wrench (spanner) and here's what I've got:

Negative terminal and cable:







Positive cable and terminal:





HPPM






There is also this set of ground attachments along the same wall as the main ground cable, I'm guessing I should remove them and clean them up too: