Hi,

I have a no start condition in my 1998 XJR which I found out this morning.
Parked the car after a short journey on Wednseday, this morning won't start. Won't even turn over.
Ok, so it says traction control fail, stability control fail, I think battery. Lets see if we can open the boot/ trunk. No problem.
ADAC man comes ( German equivalent) to AA in UK or AAA in US.
Measures the battery, 12.1V. Adds a supplementary battery, still no turning over. No starter motor chug at all.

Then I look again at all the error messages. We have:
Gearbox Error
Engine Failsafe Mode
Incorrect part fitted
Also ER from the climate control with beeping
The Shifter also doesn't go out of Park, unless you use the emergency release mechanism.

So the ADAC man proceeds to test every fuse and finds nothing wrong. So he orders a tow truck and 3 hours later I'm back at my old house outside of town where the car can stay for a while.

Prior to this I installed a heated seat switch and relay. The relay was kinda loose one morning so I just shoved it in, didn't think to remove battery connection.
Also as I was working on the centre console to install I'm wondering if I could have caused something there?
For 3 days after the install it worked fine, no issues. Only when I came back after parking for 3 days it shows this issue.

I've tried:
Changing back to original non heated seat switch, no change
Multiple hard resets, including turning the key to the on position to make sure I got everything, no change

I'm not really sure where to go next? I wanted to try resetting the inertia switch but couldn't find it where exactly is it on a LHD model?

Also I can't read codes as the OBD port is not working. Neither with my PLX Kiwi or with the ADAC pro tool. It was working last Monday.

It feels to me like the car is running through its system check and something gives a bad answer, so it goes to Failsafe mode.
The only other thing I can think is maybe when I installed the relay for the heater I either cooked a module (BPM? How to test) or managed to disturb wires which hadn't been moved in 14 years and now the seat is causing the issue? Again, how to test?

What is the significance of the gearbox fault message? As I wasn't completely finished with the install of the heated seat switch I have the ski slope not in place.

I haven't checked the brake lights yet, so I need to complete that, thought just hit me now.

One last thing, at some point somebody has worked on the radio, there is a notice of some circuit diagram in hand on it and one of the tabs for the screws was missing and replaced by black gooey stuff. So maybe there is some non standard wiring of the phone or so?

Thanks for any ideas of what to test next. All I wanted was a warm butt for winter, I guess I just didn't work carefully enough. :-(
FWIW car is in Dresden, Germany. There is a Jaguar dealer here, but I want to keep that as a last resort.

Lincoln

 

For me the clue here is 'centre console'. I've seen the 'scroll of death' when every known fault message appears.

Remove the console again and check all the connections. Then slacken the two selector nuts on the gearbox and run the selector through it's full range. When it feels it's in the right place, selecting each gear in one with the cable and gearbox it's self, then tighten up.
Try the ignition before you replace the console as further tweaking may be needed.
Hope this helps.

 

I'm wondering if the false bulkhead stud connector has failed in the engine compartment-this supplies the power to the starter & is also the main charging line from the alternator to the battery.

If this connector fails, then there will be no power supply to the starter motor & it will not turn over. Also, the alternator will not be able to pass it's charging current to the battery, so the battery voltage will run-down & throw up the Traction Control/Stability Control faults as the battery voltage is too low due to lack of charging current.

Your symptoms point towards a main power bus failure somewhere, which is causing all these faults-so it would be worth checking the engine compartment false bulkhead stud connector for electrical continuity & mechanical condition.

 

Sean B, thanks for that. I'll adjust the gear lever and see how that goes. It's conceivable I nudged it out of whack when I was pulling the centre console out.

Red October,
Also thanks for your reply. I was nervous saying to the tow truck operator to leave it at my house, but I had confidence that the combined knowledge on here would help me out. :-)
If that was the case, would I have 12V at the input side of some of the fuses in the engine bay? Cos some of them do. But I'm not very familiar with the electrical connections in the car, so maybe I'm missing something?

Thanks

Lincoln

 

The main power distribution for the X308 is as follows:

1) The battery connects to the input of the boot-mounted High Power Protection Module & this module has 2 output studs.

2) The first output stud is the high current main supply wire to the starter motor & also the main charging line from the alternator to the battery once the engine has started. This power line goes to the false bulkhead connector in the engine compartment & then to the starter & alternator-it does NOT supply the power to any of the 5 vehicle fuse boxes. If this power line fails for whatever reason-and it's usually at the false bulkhead connector-then there will be no power to the starter motor & no charging current from the alterrnator to the battery.

3) The second output stud on the High Power Protection Module has 2 connectors on it. The first supplies power to the boot/trunk fuse box, and the second supplies the power to the rest of the fuse boxes in the following order: RH Heelboard Fuse Box, LH Heelboard Fuse Box, Engine Management Fuse Box & finally Engine Compartment Fuse Box.

The power supply line to the 5 vehicle fuse boxes is NOT connected to the main supply line for the starter motor & alternator. So if the false bulkhead connector fails then there will be no power to the starter or charging current from the alternator. HOWEVER, the rest of the 5 vehicle fuse boxes will still receive their main power supply from the other route.

Before doing any detailed fault-finding, it would be worth checking that the main supply voltage is present at the input terminals of all 5 fuse boxes, and that the power is present at the false bulkhead connector-also at the main starter motor input terminal.

Any corrosion or loose electrical connections along the route of the main high current supply through the false bulkhead connector to the starter & alternator WILL cause starting & charging problems, as the currents along this wire are so high. If this main power line fails, then the starter will not work & the alternator will not charge the battery. However, all the 5 fuse boxes will still receive their power from the other supply route but, because the battery is not charging & the voltage will be low, the vehicle's electrical systems will all throw up spurious faults due to the low system voltage.

The first step in any electrical fault investigation is to examine the circuit diagram & check that the main power supply is present at ALL fuse boxes & modules through the whole vehicle.

 

Thanks Red October,
We have power at all 5 fuse boxes for sure.
But I haven't check the other power route. Didn't know it was a separate route.
Will check this and let you know.

Thanks

Lincoln.

 

Thanks. I even couldn't say it better!

Funny,.....I switched my climate control just few weeks ago (to get my seats heated), didn't even know there is a relay for that (BTW, where is that relay located?), and never disconnected the battery. My seats heat like they should, and I didn't have any issues.

Like you,....I think something else is out of whack, nothing to do with center console, and the power supply to the starter IS the first suspect. The second one would be the ignition switch.

 

Thanks Daniel,
The only thing I find weird is that there are so many error messages, if all that is wrong is there is no voltage to the alternator.
BTW: where can I access the alternator? From underneath? Which side?
I don't have a ramp, but I can fit under smaller cars :-)

Thanks

Lincoln

 

The fuse box power line & the starter/alternator power line are both completely separate from each other-they take different routes out of the boot-mounted High Power Protection Module, which is just basically a big fuse

The power for the starter & alternator goes to the false bulkhead stud in the engine compartment, and this is a potential failure point in the electrical power route. The current along this wire & through the bulkhead stud are very high-easily over 200 amps when cranking the engine on the starter & around 50 amps or so when the engine is running & the alternor is charging the battery & supplying all the power to the vehicle electrical systems.

If this power line goes down for any reason then the starter will not work & the alternator cannot supply charging current to the battery-so the battery goes flat & the low system voltage causes the vehicle systems to malfunction, since they are all still getting power from the fuse boxes which have their own supply route from the battery...

A multimeter & a circuit diagram is all you need-the circuit diagrams are on the JTIS which is available on this forum anyway

 

If the alternator isn't charging the battery, then the battery voltage runs down & so all the vehicle electrical systems start to malfunction.

The alternator is accessed from under the vehicle-it's on the RH side of the car (passenger side in European & US vehicles) right at the bottom front of the engine-it's in an awkward place...

 

Thanks Red October,

I'll have a look for it tomorrow. I have the JTIS on my laptop in the office, so I'll pick that up tomorrow too.
As to the alternator not charging, that could be, but even with the ADAC mans extra battery on the car, and after a hard reset, there was still a bunch of errors.
Makes me think it isn't primarily voltage related, but I will check these items too.
Thanks again all for all your help guys, I wasn't at all sure what to do next.
Now I have a clear plan of attack.

Thanks

Lincoln

 

In your first post you stated that the engine wouldn't even turn over under any circumstances-that made me wonder if there was any power getting to the starter motor itself, which then made me wonder if it was the false bulkhead stud connector.

There's no easy or quick way to solve electrical problems on cars with complex electrical systems, unfortunately. If it's an unusual fault that nobody else has seen very much of in the past, then there's no easy answer.

What you have to do then is gather as much technical information as possible & learn how the systems actualy work. Once you understand how all the systems work, then you'll have a better idea of what to look for when there's a fault.

I spent over 20 years doing electrical & electronic fault-finding on aircraft communications systems. Quite often you'd get faults that could take several days to pin down-even when you have all the circuit diagrams to hand & spend a full working day in the workshops on the problem.

But one thing we all learnt-and this was always at the start of the actual manufacturers test schedules-is that you ALWAYS checked that the main power supply rails were present where they should be, before going any further with fault-finding.

If you had a multiple system failures, then it was often a grounding problem or a power supply rail that had gone down or was under-volting. Over-volting would usually cause smoke, interesting noises & other forms of unpleasantness

 

My suggestion is worth a look first before getting down to fault finding.

I had this fault show up after installation of the complete wiring system on the XJR. Adjusting the gearbox selector fixed it.

The incorrect part fitted is no comms to/from the ABS module and the no start is on comms to/from the TCM. The car will not crank in this state.

Did the heated seats work OK

 

Sean, that's the bugger of it, they didn't appear to work.
At least I couldn't convince myself that it was so.
I was gonna do some current draw checks, see if anything is running over that fuse, but well this issue beat me to it.
Maybe it was only US cars got seat heating pre-installed? Mine is an Italian car I reimported back to Germany. They have a crazy tax on anything bigger than a
Fiat 500 there now, so I was able to pick it up for a good price.
Cheers

Lincoln

 

Oh, Daniel. The relay was under the drivers seat on the left hand side of the seat.
Seems weird if yours had one pre-installed, I thought the penny pinching went further as the years went on?
Maybe not on US models, I think the ordering process is somewhat unique there

Lincoln

 

Shouldn't be too hard to check that the supply is present at the false bulkhead connector, before rolling around underneath the car probing the starter & alternator

 

Red October,

I hear you on the electrical faults, I used to do something similar on semiconductor tools in a cleanroom environment. Not fun.
The ADAC man was looking for the starter and the alternator and let out a sigh and a swear word when he saw the engine compartment. I quote "it's all engine, there's no room for anything else"

Sorry it's not a Golf :-)

Lincoln

 

I know-I hope the alternator or starter don't fail on mine, as it's not going to be a fun job to replace

 

I seen those codes when I was playing in the centre console too and by mistake I turned the ignition; there are some micro-switches that are pressed by the gear lever, to let the computers know which gear is engaged. Have a look there and see if the connectors to the car's harness are right or if the switches are broken or missalligned. You can put a picture here with the J gate.

 

My cat is a 98. I still have the original seats in the garage. I just flipped the driver's seat over, and there is a square (brown) plug that looks like something could be plugged in it (but it wasn't). There is no relays. The seats I put in my car are from 2003 model, and the driver's seat has the same brown plug, with nothing plugged in it!

I replaced the climate control first, and turned it on. Both old seats were getting warm. I installed the new seats, and plugged just one white plug (the bigger one), and a little black one (as far as I remember). Nothing else was done. To get the climate control out, I had to unplug the radio, and pull it out (but not all the way). To unplug the harness for the climate control was PITA, and I ended up bleeding (now I know why there are so many climate control units on Ebay with cut harnesses!). All this was done without disconnecting the battery, and it worked like a charm. It's heating good, no radio code was needed, and all is good. I thought about replacing the back of the center console with the switches for the back seats, but decided against it. Nobody ever sits there, and RARELY my wife sits in the front passenger seat (when we go somewhere together, we use one of the other cars).

I would check the power first (bulkhead connection is easy to check), and then fiddle with the gear selector. I don't know what you did while replacing the climate control switches, but all I did was take off the shifter knob, shift in D (to make the room for the radio to come out), took the bezel and the ski slope off, and unbolted the radio and the climate control. Gear selector switch was not molested or disturbed at all.

What doesn't make sense is that you replaced the climate control and the car drove fine for few days (if I understood your post correctly?), and then you had "no start". If you buggered up something during the install (gear selector switch), the "no start" would show up right then and there.

Good luck, and tell us when you solve it.