XJ8 2000, The battery is going flat after 2/3 Days, have found that parked up it is using 2amps, taken out fuse 9 right hand rear fuse box, which is a radio fuse, now down to 0.8amps. Anyone had this problem before?

 

Shouldn't even be drawing 0.8 amps, parasitic current is of the order of a few tens of milliamps. Should go for weeks before sluggish starting sets in. My Sovereign X308 stood outside unused for nearly 4 weeks in December and January in all the snow (UK) but still started first turn of the key on first crank. Aerial not retracting properly perhaps?

Jim

 

Got the Current down to next to nothing, must be a fault with the radio, when i was fault finding the Radio switched it self on, with the key out.
New Radio?

 

Sounds more like accessory power problem. The radio shouldn't be able to get any power with the key out. Maybe someone re-wired the radio, or maybe ignition switch?

I could be wrong. I'm going by my 1966 Mustang since it's basic wiring 101 and the Jag is definately a different animal. hehehe

 

There are several things in the Jag that DO require quiescent current with the key out, including the radio - but the current you are seeing (both for the radio and without) seem somewhat on the high side. Something is definitely drawing parasitic current when it shouldn't. Anything over, perhaps, 0.1 Amp should be a concern. (100 amp hour battery, for example, would then last for 1000 hours - at your original 2 Amp draw, no more than 50 hours).

It's time to put your Amp meter in series with the battery and start pulling fuses (I know, there's a lot of em), to see what is causing this.

Do you have the electrical diagrams - they will help you identify what fuse is driving what components. Available here:

http://www.captainjaguarscathouse.co...ec%20Guide.pdf

Good Luck!

EDIT - just saw your last post about the radio - now a question due to some confusion:

Did you pull fuse 9 from the TRUNK fuse box or the LEFT or RIGHT side rear HEEL BOARD fuse box?


Fuse 9, LEFT HEEL BOARD fuse box is radio head unit - this would point to issues with the radio - or, perhaps with the antenna - see below.

Fuse 9, RIGHT HEEL BOARD fuse box is rear seat heaters - likely unrelated unless this is the one you pulled to get current to go down.

Fuse 9, TRUNK fuse box drives ONLY the power antenna - may be the problem as Jima suggested. The radio being on will cause the antenna to be powered and attempt to rise (or lower when radio/key switch is turned off - if the motor stalls, 2 amps is very possible). Pull this fuse, with the radio fuse in place, if current goes down, it's the antenna, if current stays high, it's likely the radio.

The radio also gets SWITCHED power (on with the ignition switch) from fuse #3 in the TRUNK fuse box. Without this, (key off) the radio should not turn itself on... unless - Do you have Navigation? It is possible that the NAV is turning the radio on...

 

Anyone figure this one out my radio is staying on with the key out.