Odd electrical issue + battery power leeching 2001 XJ Sport
 

So this one has me stumped. I couldn't find any info on this as it does seem very odd/unique. Turn signals and power windows don't work when the car is running/driving. If i shut the engine and turn the key back so there is just power, the turn signals and power windows work. What could be causing this?

** power leaching is NOT happening.. what is happening is i started checking stuff before i had my coffee. I had the wires on the meter backwards.. sigh...coffee time... battery has a full charge.

Battery voltage of 0.01 is not possible in a car that until recently has been driving..

And what do you mean with battery died? You mean your engine stopped running or you lost power?

yea..you are 100% correct. i edited my post.... went out this morning before my coffee... my dumb ass had the wires in the meter backwards. I must have stuck em like that when i put it away months ago and didnt even look at them lol. I have since had my coffee lol.

Basically, i bought this XJ Thursday. Drove it home, (on the way home i noticed the turn signals and windows were not working and the check engine light went on). I put it in my drive way, the next day i went to start it and ignition sounded weak like it was struggling to turn over and sounding like it was cranking very slow. Tried again and i got the fast clicking sound. The battery was old and the car was sitting for a few months through winter, so i figured it cant hurt to get a fresh one. Put in the new battery. Tested the old one after i took it out with the meter with the wires the correct way lol and it read 12.09.. So that had me scratching my head. Hooked up the new battery (tested at 12.24) and well, it started. Also it seems turn signal, window issue, and check engine light resolved itself at the same time. I did clean the connectors as well so that may have played a factor as well.

You should inspect the ground cable from the battery to the engine block. It's very common for them to corrode under the insulation and they're relatively cheap and easy to replace. Typically the issue manifests itself when a vehicle won't start, clicking sound only. Owner twists the battery terminals and vehicle starts. Owner thinks they just had a bad connection. The actual issue is generally the ground cable corroding. The moving of the cable when twisting the terminals is enough to get better contact inside the cable, allowing it to work for a bit longer.

Also not a bad idea to check the ground strap running from the firewall by the wiper motor down to the engine. Normal maintenance stuff... It's never a bad idea to take out the bolt and clean the surfaces to bare metal.

On earlier model XJs, the dash grounded through the metal structure of the dash. Adding a short length of wire from the metal structure over to the kick panel works wonders. I assume the newer XJs are similar in how they ground...

ah! good to know i will check that! It does seem easy to replace, and anything easy to replace i should probably replace! lol Thanks for that tip!