hello dan314.

there are 3 rules about doing any electrical work on a jaguar.
1. disconnect the battery
2. disconnect the battery
3. disconnect the battery.

you do not have to remove both cables on the battery -- just the negative, braided cable. then tuck it onto the side or cover with a rag. anything to make sure it doesn't accidentally touch the negative battery terminal.

then, if there is a connector anywhere on the yellow wire, by all means disconnect at that connector AND use electrical tape over any exposed wire or contacts.

then re-connect the battery and see what happens.

if you're nervous about dong this, go to any after market radio shop and give the kid $20

best regards bob g

 

Thanks Robert,
The wires are attached by the tightening nut on each battery main terminal connection. Means that I’ll have to loosen both terminal connections to remove the piggyback wires but from what you’ve told me that’s ok (as long as I disconnect the negative terminal first).

 

Correct. On your Jag, always disconnect the negative first and then the positive. When reconnecting, connect the positive first then the negative.

 

Many thanks!

 

hello dan314. status?

 

Hey Robert,
Once you told me there are no other connections than main pos and neg cables listed in Jag Tech Docs, I disconnected (neg first) piggyback wires on battery terminals which powered an “add-on” Sirius Radio system. Couldn’t see any obvious shorts (but it’s my opinion after reading hundreds of electrical fault postings in the a Forum that electricity is basically just magic). No faults occurred and she’s cranking great.... so far so good.
Thanks again for your intel.
Dan

 

Wait, this car cannot be jumpstarted? That's good to know.

What harness does it destroy? Are you talking about the wire harness directly attached to the battery? I'll have to inspect mine now after trying to start it and having the same issues as OP.

 

What post above leads you to that conclusion?

 

Before I discovered / disconnected the ‘add on’ Sirius Radio power leads, I had my ‘05 XKR jump started a couple of times (with AAA boost pack) and suffered no problems at all. Can’t speak to earlier / later models.

 

The way to jump these things is what's called (by some) a "dead jump", whereas the dead car does NOT have the ignition on, but merely receives voltage from the supplying vehicle. Once a period of time has passed, the cars are disconnected and the 'dead' car is started.

 

It's here

 

Yes you shouldn't do it. I'll see if I can find the article. Was an Australian article and Jaguar indicated to the writers that jump starting off another vehicle can damage the engine harness. So use a portable lithium Ion charger or a dead jump as Cee Jay indicates.

Edit:
Here's the article.
https://www.mynrma.com.au/cars-and-d...ot-a-good-idea

 

Rather a junk article. Best ignore it and stick to what Jaguar say.

 

?
from the article:
"Jaguar warned us that you could damage the whole wiring harness if you try to jumpstart one of their cars, and that warning is probably applicable to most vehicles built in the past five years."

It's not just Jaguar. This applies to most all modern cars, certainly on the high end. There are so many viable LI battery pack options now days, there's no reason not to stock one in your boot.

Ultimately when push comes to shove, you gotta do what you gotta do to get up and running.

 

It's a not-very-disguised ad, designed to sow fear.

If you can connect a (Li or other) battery pack you can connect another vehicle's battery.

No need to start the other vehicle.

 

From what I've read the issue is regarding having the donor vehicle running during the jump start. It is recommended NOT to have the donor running. That's what I've seen.

 

This is the method I’ve always heard to ‘jump start’ these cars. The donor car’s battery is like lugging a spare battery over to your dead car, and connecting in parallel.
I hadn’t heard of the ‘dead jump’ method described by Cee Jay, but its using the donor car as a ‘battery charger’ on the dead car.
Both should get the dead car started. The first will get you going faster, the second might give you some reserve if you happen to shut off the car before you get to your destination to change or fully charge your battery.

 

So, as per the posts above, yes you can jump start the car, but both vehicles should NOT be ‘on’ at the same time.

 

I've read that multiple times too, though not Jaguar specific. If you have to jump using another car, make sure the donor car ignition is off. So for me personally, I have a garage queen of a car, that's on a maintainer and healthy battery. I keep an LI jump starter in my trunk. So bring it on Jaguar!