I have just read a thread about not using a second car to jump start a XK8 but to recharge the battery as the only way to proceed.
I did not know this at the time and about a month ago when I was getting my seats colour matched for repair, I had a flat battery on the XK8. I jumped it with my XJS, it started straight away. Now with the knowledge of possible damage to the sensitive electronics I was wondering if anyone could give me an idea of the kind of damage to look out for please? Looking for things to check which could have been damaged. Fingers crossed and everything else.

 

I don't see why the XK8 should be any different to any other "modern" car for jump starting.

Does anyone have any evidence of "sensitive" electronics on this car that are poorly protected or is this just a myth.

So far, just about the only reliable thing on my car is the electronics!

 

Arty,

The two things to avoid are:

1. running the engine of the 'jump' vehicle
2. allowing contact between the vehicles

The risk is a 'spike' which could fry the super sensitive electronics in the Jaguar.

I'm sure many owners have got away without any damage on numerous occasions but the risk is real. We had one member here within the last year who had serious issues with an Instrument Pack following a jump start.

If you had been unlucky when jump starting last month, you would be basking in the warm glow of warning lights or have dead functions and a catalogue of error codes by now.

Graham

 

What GGG said. Just to flesh this out a little ...

1) If the car we're getting a jump from is running, and the jump is successful, then we will have the alternators and regulators of two running cars sort of fighting each other. Not so good.

2) Be sure ignition set to Off position (both cars) before attaching cables. Hook up the "hot" cable first, then the ground cable. The ground connection should be completed not at a battery, but somewhere with good frame contact away from a battery if possible. The last connection made should be the first one removed. The reason here is that the last connection may spark when connected /disconnected ... and a charging battery makes hydrogen ... and it's best to assure that the two never meet.

There's no reason not to jump start our cars (any car) so long as we're careful about how it's done.

 

The other problem with jump starting is the proliferation of cheap jumper cables with wires that are not of a heavy enouh gauge to carry the starting current without excessive voltage drop.

This can cause the voltage during starting to dip so low that various computer modules begin to malfunction.. Usually a hard reset with a good battery will resolve any problems caused by this.

One way to avoid this is to have the donor car charge your battery first for say, 15-20 minutes, before attempting to start (assuming your battery is healthy enough to accept a charge).

 

I've jump-started many friends' vehicles over the decades without any issues. But if I ever have to jump-start either of our Jaguars, I'll do it strictly by the book due to the sensitive electronic modules. My biggest concern regarding this topic is that my wife's XK8 suddenly requires a jump-start during one of her trips to Florida and the AAA guy who shows up to do it refuses to follow the procedure as it is spelled out in the owners manual....

 

Many thanks for all the comments guys, hopefully I have got away without causing any problems.
Cheers, ArtyH.

 

 

Ouch! Sorry to hear.

Spikes and sparks tend to occur when a cable is removed (for the same reason a breaker-point ignition system fires when the points open).
Having both ignitions off when making or breaking jumper connections is a really good idea.