Where (and what color wire) is there a switched groud location under the hood? Preferrably left side and easily accessible to tap into. I'm no wiring expert but damn, these cars are a f'n pain in my *** trying to wire up switched power. I'm getting power from a positive stud at a fuse box on the left of the engine. I need a switched ground wire. At least I think this is the way to do it. Either that or switched power.
one of the two relays to the left of the radiator maybe? Or the big wire loom in the brake boost/resevoir compartment on the left side that runs to front of the engine compartment. Tired of sticking my fingers with my probe and getting nowhere.
Thanks in advance.

 

Do you have the electrical guide for your MY car?
JagRepair.com - Jaguar Repair Information Resource

 

The two relays at th front of the engine bay are the wiper on/off and high/low speed. The wipers don't work with the engine not running, so you should be able to tap into one of the supplied there - I'm assuming that the wipers use switched power not ground.

 

I'm pretty sure a relay uses a switch ground. Either way that's one of my first choices. The other thing I might do for more than one reason is open that big loom I was talking about. For approximately 6" just inside and outside the left side brake compartment it just taped anyway. I could tap into the wiring for the wiper relays here most likely. It would be hidden and protected better there. Either way I'd solder and shrink wrap.

 

The relay furthest to the left, wiper start/stop if I remember correctly , there's a red wire with what I think is a blue stripe that's switched ground if anyone is interested.

 

Download the wiring diagram -- if you can't find it, let me know and I can send it to you.

 

I did but thanks. I just can't tell at a quick glance if the red wire I'm talking about has a blue stripe.
But the schematic does show a red/blue(RU) as being a switched ground. This was verified with my probe. Hooked it to the positive terminal feeding the smaller fuse box and poked that wire with the key off...nothing. But she lit up with the key on.
I just have to wait til the weekend to get this done and I'll verify the color of the stripe at that time.

 

Well ****. It's not the red wire. It's ground all the time. Back to square one trying to read the schematic with my failing eyes and poking my finger I guess.

 

The diagram on Fig. 02.1 for the ignition switch shows a convenient wire to tap-in (WY) which goes to the diagram on Fig. 01.1 to the Ignition Positive Relay in the Engine Compartment Fuse Box.