Jaguar 2006 XK8 won't start (no crank). I just bought a Jaguar 2006 XK8 a few days ago (shipped to Texas from California) and a couple of days ago it wouldn't start (no crank). I pulled battery and had it load tested - OK. Checked connections at battery and trunk area, checked fuses in RH front box and swapped starter relay there too. No crank.
I whacked the starter with a rubber mallet as best I could and it started once but not the next day, so I am thinking to replace the starter, or maybe I was just lucky?

Can security system failure / problem cause this?
Does security (key problem) give a message in the speedometer message area or set OBD/Diagnostic Codes (I have a scanner)?

R & R of starter - 2006 printed manual has directions for the earlier 4.0 L model (1997-2002) which mentiond removing the Power Steering Rack (looks to be a big hassle) but no instructions for the 4.2 L engine (2003-2006).
Computer based JTIS mentions to remove the Cross Brace and pull the starter, no mention of the Steering Rack.
Anyone done this and can confirm which is correct?

I have several questions here and welcome all answers.
Thanks,
John

 

I would spend considerable time verifying that the electrical to the starter is working before dismantling the starter especially since it rotated at least one time in your presence. I don't have any info on the '03 up cars but the previous models had a 'start' relay in the right enclosure. Swap it with another. They are all the same. You don't mention the two large 250a fuses next to the spare tire. There have been reports of loose connections there and even broken fuses due to the tire shifting.

 

Do you hear a clicking sound ? it could be a bad connection in your starter.
I repaired it using a kit from ebay.

JAGUAR XJ8 - XJR & XK8 - XKR STARTER MOTOR REPAIR KIT | eBay

 

I checked the 250 amp fuses in the luggage compartment and they are both OK.

I swapped the relay (USA LHDrive so RH engine compartment under little black cover near firewall parallel to fender and towards front, per book) with another nearby and still no crank.
I hear a click somewhere when I turn key to III (start) but can't quite tell where it is. I will get help to check relay to see if it is clicking. Harder to check starter - perhaps I will get helper to turn key with me under the car. Might also put key at II (run) and jumper contacts in solenoid to see if starter operates.

Looking into repair kit - nice suggestion and inexpensive. Your seller is in UK so it would take me 1-2 weeks to get it here so will see if I can find it locally.

Thanks for the suggestions.
John

 

I got the starter out with some serious contorting on a 2001 XK8 so it CAN be done without disturbing anything but the starter itself.

 

I discovered it is not the starter!
I was following instructions in Post #5 in this item https://www.jaguarforums.com/forum/x...er-inop-70029/ .
Starter relay socket - Bat voltage at #3 - yes; Terminal #1 power w/ key - YES; Jumper #3 to #5 and starter cranks - YES - so not bad starter but car doesn't start. Arms not long enough to hold key in III and check for ground at #2 - I will get help later on that. I am suspicious that is symptom of my problem, however.
Tried to pull ECM box from under hood on right side by/under starter relay but it has a 5 pointed star shaped screw with a raised pin in the center holding it. Now I need another tool and I don't even know what it is called...

Tested every fuse in same fuse box as well as left (Driver's) side fascia. Have swapped most of the relays at least one position and still no crank. Did a hard reset per other threads and still no crank.

I suspect electronic or mechanical item over actual wiring failures, so what should I do next, please?

Other thread mentions KTM, BCM, and ECM but not sure how to access KTM and BCM.
What about Ignition switch mechanism? How/what to check there?
If you replace KTM, does that require Key Reprogramming?
If not, which box has key memory?

Thanks, John

 

Starter relay pin 2 does not go to ground when the key is turned to III-Start.

 

Later model workshop manual likely on ebay quite cheap.

 

Got a PDF workshop manual and installed JTIS. Both are schizophrenic! E.g. make references to non-existent section numbers Section 211-05 on removing the Ignition Switch: "Remove the underscuttle; refer to Section 501-05" But 501-05 does not have a section called "Removing the underscuttle".
Never heard of an underscuttle before, either. I found something in 511-12 "Instrument Panel Lower Trim Panel" which mentions "underscuttle" so perhaps that section will do.
And then there are references to sections with completely different numbering systems, like "Working from below the vehicle, remove the power steering rack for access. Refer to Operation 57.10.01." They must have changed section numbering system and forgot to tell someone.

Then there is a note that says "Check the ignition switch function. (Switching action across the ignition switch contacts) If the switch function is normal, contact Dealer technical support for advice on possible BPM or ECM failure."
I'd like to start with the ignition switch but I can't find a section on testing (checking) it!

 

Looks like a crock (my S-Type one isn't like that). I believe other places with data include Mitchell, Alldatadiy & jag's own TOPIx.

 

Not a crock. JTIS I got from this forum. PDF of workshop manual is JAGDOCS.
Jaguar's documents are less than perfect, shall we say, but the price was not very much.
Anyway, anyone seen diagnostics on the Ignition Switch or its wiring?
I am just a poor XK8 owner still trying to figure out why my car won't start (won't crank).
Ordered a set of 5 pointed TORX tools today so I can undo the ECM wiring.
What a obnoxious thing to do to use that kind of fastener in a place like that.
Thank you,
John

 

They were trying to stop thieves easily swapping modules so they could then drive the car away, I believe. There are very few genuine issues where the PCM needs to be removed.

Technology has moved on and thieves now reprogram keys via OBD socket then can drive car! (Can you say BMW...)

 

Are the key electronics ok? Try a diierent one.

 

Only have 1 key so I must find other ways to diagnose the problem. Right now puzzling over lack to Ground at the Starter Relay. Ground is switched by the key but goes through several modules before it gets to Starter Relay. Also, there are other switches involved which I am trying to figure out how to diagnose, e.g. the transmission P/N switch. Lights indicate gear correctly but not sure if that is only switch involved. And it is hard to find where all the components are actually hidden on the car, despite charts with arrows.
Thanks for the suggestion, though.

 

Pulled out the console and checked the not-in-park switch which was good so still no start. Had it towed to a local Jaguar Mechanic who put it on his computer and told me it was a security issue.
He reprogrammed the security module and it started up OK.
It now works, but not very reassuring as I don't have any idea why it would not start for me for a couple of weeks!