Raccoons - probably the black/white striped cables.

 

Evening all,

I tapped into the yellow white cable and tested to the 54 way thru panel in the drivers footwell pin2,(FC3-2) open circuit.
Same cable to the Pin 9 (LS7-9) on the green connector 0.06 Ohms.
Bugger, the fault is somewhere behind the wing.

So I removed the wheel arch liner, and there is the connector.
When I bought the car there was no wheel arch liner here for reasons Carlo did not wish to share with me.
So maybe its just dirty or damaged, or the pin is loose and finally failed one cold morning in February (yes it is that long since this started, or failed to start).

My question for today is: How do I get this 54 way thru panel connector loose so I can
a) pull it into the footwell?
b) pull it into the wheel arch?
Any one have any experience here? Do I need to move some tabs inside the footwell, or how does it work?

Once I have the thing in my hand, I will clean it and measure the pins/wires and take it from there.
Actually looking at the picture "pin_2_with_marking" (with an arrow in it), the colour of the stuff on the white-yellow cable looks like the copper on a church roof, could be the root cause if it is so badly oxidised that it has no contact at all any more?
Anyway, I'll know more once we get it out.

Please note: in the pictures below I have seen a sum total of zero racoons or weasels. :-)

 

Update.
The cable is nothing but blue dust. I've never seen the like of it before in my life! Completely oxidised.
I'll fix the cable and come back with the result.

Thanks for all your help guys,

Chalk another victory up for the forum

Lincoln

 

So far it's more a victory for your determination.
Tracing wiring faults can be the very Devil.
Good luck with the fix.

 

Evening All,

I cut and spliced the white-yellow wire, tested for continuity and buttoned it all back up.
Those 54 way thru panel connectors have tabs on the top and the bottom inside the driver footwell, then you can push it into the wheel arch.

Turned the key, closed my eyes and prayed to the Jaguar God and ........
IT STARTED!!!!!!!!!!!!!!!!!!!

I haven't moved it yet but I'll drive it tonight and finish this thread.

@ Mods --> how do I add fixed to the title thread?

@ All --> thanks to all for your help on this one, I learned a lot about my car and the total cost was less than $50, and I saved a bunch on petrol for the last 5 weeks ;-)

Cheers

Lincoln

PS: If anyone needs pics of any of the areas I touched here, transmission tunnel, the glovebox, the steering column cowls the driver and passenger footwell, let me know and I'll post some.

 

What a journey, congratulations to you for your persevation, and that you solved it!

 

So what happened? Did Fishfoolbear ever get his kitten to purr again? Wondering, because I now have exactly the same problem: It started displaying all kinds of error messages while I was driving, the speedo went down to ripple just above 20, and then 2km later the engine stopped. I managed to start it, drove 200m, and then it stopped entirely. Had to tow it away.
Doesn't crank, displays GEARBOX FAULT, FAILSAFE ENGINE MODE, INCORRECT PART FITTED. OBD2 doesn't connect to ECM. Checked under radio; nothing seems wrong. Guessing this is a case of shorted or open circuit CAN bus; daunting. Please help!

 

Hi og3930,

Fishfoolbear's (real name: Lincoln) Jaguar is back purring nicely. Just got a picture from my friendly policeman today to prove it.
First off, I'm on Central European Time based out of Munich now, if you are anywhere near I can come take a look. If not, PM me and I'll sned my mobile. Fixing that problem was a huge pain, but I think my dialogue with the forum helped to formulate my plan and having someone check the logic is always good.
--> Just seen you're in Oz, that's a bit of a trek from Munich.

So, to your car.
What happens when you turn on the key, like position 1, any lights (I assume yes, as you can read the "scroll of death" but please confirm).
Do you have an XJR or XJ8? The XJR makes a whirring noise before the engine is cranked over, I think its a cooling for the supercharger.
Can you hear that?

I'm going to go take a look at the electric diagrams (available on here or at JagRepair.com - Jaguar Repair Information Resource) Be sure to get the right year as AJ26 and AJ27 are different in some critical areas.

If you don't have a mate who has unlimited time to watch you mess about and tell you if current is flowing, I suggest making a "voltmeter for dummies". Get a 12V klaxon or horn and put spade connectors on it. Then stick that into the connectors of the relay you wish to test and if current flows it goes BEEP, if not silence. It's handy for the jobs you'll need to do.

Be back on later with some first tips.

Cheers

Lincoln

 

Usually you get the advice to check the following things, in the following order
1) Battery: check if it is charged 12V? Should be more like 12.9V I think. If you can have someone crank and you measure across the terminals, what is the voltage drop?
2) Bulk head connector, this brings the 12V directly to the engine compartment. Do you measure 12V here?

After that I like to look at the problem backwards.
The starter motor does not turn, so let's look at that.
The 12V comes directly from the bulkhead connector to the starter motor on a big fat brown wire (N in the diagram). Do you measure 12V there?

If yes, then let's look at the starter relay, this gets its power supply from the fuse #2 in the engine managment fuse box , 25 Amp fuse feeding a Brown White (NW) wire into the relay.
Do you measure 12V on the input side of the relay?

If yes, then how about the cranked side of the relay? The input 12V is supplied from Fuse #5 Engine Compartment Fuse Box (note different to engine managment fuse box above) on a White Pink (WK) wire. Is there 12V here?
Then the start signal (switched ground) is sent by a conglomerate of Body Processor Module, Key Transponder Module, Ignition Switch, neutral switch and Engine Control Module on the green orange (GO) wire.

One easy test is to short the White Pink (WK), input 12V to the starter relay to a known good GND and see if the starter turns. Don't worry, you won't start your car, petrol won't flow and there will be no spark.
Be careful what ground you use, don't fry any electronics.
Does it turn? If yes, forget about the starter as an issue and concetrate on the inputs required to get the switched ground signal to switch to ground.

One good way to check the switched ground signal on the starter relay is to connect your voltmeter for dummies to a known 12V, stick the other connector into the green orange (GO) cable end of the starter relay and turn the key. If it beeps, all is well in your expensive module world. If not, we may need to dig further.

Let me know if any of that makes sense.

Cheers

Lincoln

 

Lincoln,

Thank you so much for all your support, the "detective" work you did last year was impressive and I am really grateful for the effort you put into answering me yesterday.

My XJ8 started less than an hour ago, it feels a bit like a miracle resurrection. In my case it was a bad connection in the 54-way connector in the LH A post. In particular the WY cable pin looked burnt; it shouldn't carry too much load, just the relay coil, but still. After a good clean and a bit of fiddling to get it back together (REALLY fiddly!) it worked. Now it's just a case of putting back all the other pieces that I had taken off it (was barking up the wrong tree entirely to begin with; I thought the gearbox cables were faulty).

Your advice was really crucial for my success, in particular your conclusion about the reason for the GEARBOX FAULTY/FAILSAFE ENGINE MODE/INCORRECT PART FITTED messages. That's what made me look for power from the IGN+ relay.

BTW, I wonder who at Jaguar Cars wrote the messages. INCORRECT PART FITTED should really read ECM NOT RESPONDING or something like that, do you agree?

Thanks again! You now have a fan in Melbourne Australia (a few timezones away).

OG

 

Just another question: Does anybody know if the 54-way through panel connector is available from somewhere? In case it plays up again I will try to replace it. Or will I have to replace both looms? (That would be a big job indeed!)

OG

 

Hi, first time poster long time lurker.

Couple of weeks ago I drove my 1997 XK8 back from office without problems, but the next morning I got the Christmas tree of warnings:
- Engine Failsafe Mode
- Incorrect Part installed
- Low Break Fluid
- ASC/Trac warning
- Gearbox failure
- The shifter also didn't go out of park.

I came to this forum to look for clues what to do and got some tips that battery could be an issue. I had an old battery so I charged it for eight hours, but after disconnecting the charger car would still not start and all the warning lights were still on. I decided to leave the charging on while wondering what to do next. After 16 hours of charging I measured the battery voltage and it was 12.82V which is good. After disconnecting the wall charger again I tried to start again and car started, but two warning light were still on and car was not running smoothly.

I measured the battery while the car was running and it showed 14.5V so car was charging the battery. Still not sure what the issue was I decided to see if the battery holds voltage. The next morning battery voltage showed 12.10V and the big drop meant that the battery was bad.

I got a mobile battery service to come and swap the battery and they could see it was a 6.5 year old battery. Often batteries have a date stamp on top or side of the battery which you can also check.

I hope that helps anyone with a same problem. This forum certainly helped me.

 

I'm so thankfull to the members on this forum who are sharing there wisdom to help others


I had just finished putting my engine back together when i got the same bunch of error codes on my display , transmission / wrong part installed etc.

Resetting the inertia switch solved my problem
Probably the switch tripped when hacking away some rust on that side of the car..

Without this forum i would NEVER got the idea to search in that direction

 

Had exactly this issue today. Long sequence of events stemming from a blocked cat, and that stemmed from decarbonising the engine, because of excess compression (175psi) most probably due to oil leaking into the cylinders.

Any how, turning over the engine several times appeared to illuminate the Christmas tree lights of jag death, ie gearbox fault, suspension fault, incorrect part fitted, and finally failsafe mode, along with zero response from the ignition.

I swapped batteries for a brand new duracell one, but that didn't actually work straightaway. I proceeded to wiggle the larger cables near the fire wall as mentioned. That worked!

I've never had this very significant issue from a low battery and I'm still wondering if that's what caused it!

 

Yes, low battery or bad connections in the main cables from the battery will cause the kind of messages you experienced. You should undo all main cable connections in the engine compartment, including at the fuse boxes, and give them a good clean up. Other cable connection points to inspect and clean are those in the boot, at the master fuse box. The crimps on the cables at the clamps to the positive and negative battery posts can also develop internal resistance (although they may look very good on the outside) and cause reduced or fluctuating voltage going to the engine. The way to check these crimps is to touch them immediately after starting the engine - if they are cold or lukewarm, they are ok; if almost burning hot, they are no good.