I left the Jag sitting for almost 2 weeks under my car port. The battery was dead when I started to take it for a drive earlier. I have never had a problem like this before and have left it sitting for a week once before. Something to note is that I just replaced the cigarette lighter fuse a few weeks ago. Is there a common problem of battery drawing related to the cigarette lighter power circuit? Is that circuit energized when the key is off? Thanks in advance.
-Rob

 

Hi rob,
Presumably the original cigar lighter fuse had blown as you needed to replace it?
Did you replace the fuse like for like? A post has been made on here and other forum sites with reference to poor quality replacement fuses and the problems they can cause.
Draining the battery was one of the complaints.
If I may suggest checking for current pull at the battery with the cigar lighter inserted and removed?
This may help to diagnose a faulty element or housing.
Alternatively replace both the housing and the element with a breakers part.

Dom.

 

I have heard about problems in the 90s from cheap mini (ATM) fuses, which this car doesnt use. Thats a good idea on the current draw test. I think I will do that whenever I jump this thing off and take it to the shop. What is a breakers part? I was actually thinking that another component may run on the same circuit as the cigarette lighter and that was causing the draw, but that sure may not be the case. Thanks, you da man.

 

I don't see how a poor quality fuse can create a draw. A fuse is simply the weakest link in the wiring that either has continuity or does not depending on whether the fuse is good or blown. They are in line to prevent a fire in the event of a short or an overload of a particular circuit. There are different amperage ratings of them to cover a wide range of applications. Most fuses will be responsible to cover more than one operation so when a fuse does blow, other electrical items will not function including the one (or the wire) that is at fault.

I do agree to do a draw test to find out which circuit is the guilty party creating the draw. Disconnect the negative battery terminal and put the meter between the battery and the negative wire, and read the draw. Have someone else watch the meter as you pull out the fuses one by one. I would start with your cig fuse because it was the last thing touched. When you get to the fuse that makes the draw go away, look in your owners manual to see exactly what it is responsible for. You must then isolate each component from that fuse to find out where the draw is.

This can be a frustrating procedure. Owning my own auto electrical shop for 13 years has given me the pleasure of doing this many times. I even rewired a car that was pulled from the bottom of the Delaware River. I made everything work, but it smelled like fish!

Good luck.

 

The cigar lighter is not powered with the ignition off so you are going to have to look elsewhere for any current drain. When you get it running you might have an auto parts store do a load test on the battery. Might be time for a new battery.

A 'breaker' is a British term for an automobile recycling facility (junk yard).

 

Agreed - Neither cigarette lighter is powered with key off, at least in every XJ8/R year I've looked at. Your year and model (just to be sure)?

 

I will load test it myself at the shop. The battery was replaced right before I bought the car, but it is an autozone piece of junk! I guess I will have to dig into the wiring diagrams and see what else runs on the cig lighter circuit. My model is a 99 VDP.

lol that's awesome on that Delaware river re-wire Sometimes, installing harnesses is a pain in the ***.