Okay guys there has to be someone on the forum that can help me with this one. My other car (Chrysler) has a battery drain when the ignition is off about 30millivolts which as far as I know would be normal with car running an alarm system which monitors all the time however my XJR has 0.8 volts with the alarm system off so would anyone on here know what the normal should be. My Jeep has 0 volts loss but nothing is running on it once the ignition is off..

Thanks

 

I assume you mean milliamps and amps? My xj6 has a current flow of about 300 mA for a few minutes after shutdown, but has reduced to about 25 mA after an hour, as I recall. When it drops in that hour, I do not know. As I recal, others have reported that the immobiliser switch in the main key hole could be to blame if it sticks on, but there is no imobiliser in US spec cars. I think Canadian cars are the same as US.
I am positive that an 800 mA drain is indicative of some problem, and I would pull fuses untiil I found it, if I were you.

 

Thanks for your reply but I have a resistor that i can use for testing milivolts in the battery along with a multimeter. Thanks..

 

Mine sits at 40mA. It has the Jaguar alarm system installed.

https://www.jaguarforums.com/forum/s...ad.php?t=41880

 

Well you can validly test current draw by reading millivolts across a resistor, but you are still measuring milliamps.

 

Sim, like was mentioned, you have a current draw of some form. The easiest way to figure this out is to connect your multimeter inline with one of your battery terminals (either measuring current directly or via your resistor method-both work). Then you will need to remove every single fuse (note which ones go where) and also every relay (again, note which one goes where). You should see the multimeter drop to 0 milliamp/0.000 VDC draw. If not, you have a wiring problem with the main harness. From there, install the fuses one at a time, noting the current/voltage drop after each installation. If you get above 40 milliamps, remove the last fuse installed and then continue installing the rest. Once all the fuses are installed, install the relays one at a time. Again, checking the multimeter between each install and noting that current has not gone above 40 milliamps.

Once you get everything reinstalled, except for the fuses/relays that cause the current to rise above 40 milliamps, let me know what fuses/relays you have left out and we can narrow things down from there.

This isn't the fastest way initially, but it will garantee you find the issue using common tools.

 

Okay Guys tell me if I am infact doing this right. I had my Multimeter set to 200ma one lead in COM the other in the un-fused side I then went from the battery + to the +cable and it read 9.2 and I belief that is milliamps is it not? If I but the meter to the 10amp and open the door so the light comes on when I connect the meter the same way as above I get 2.2 amps. I also tried getting a reading from the fused side of the meter but it only reads 1.. Which I find a tad strange..

Any input please..

 

Sim:
You can either read current directly with your DMM, or you can, as you previously posted, read the voltage across a 1 ohm resistor that is in series with the current. If you do that, then the voltage you read is equal to milliamps due to the equation e=I*R with R being the 1 ohm resistor.
I am not sure what you mean by "unfused side", but I assume you mean the separate DMM probe socket for mA (milliamps).

I am assuming you have some meter like a Fluke 97 for hthis explanation-
To use the DMM to measure current, disconnect the battery positive lead, connect the red DMM lead (plugged in to the 10 amp DMM socket) to the battery + post then connect the DMM black lead, plugged in to COM to the positive wire previously dis-connected from the battery. Now read Amps. If the amps reading is less than 1 amp, reconnect the red DMM lead to the mA DMM socket to read mA (which is, of course 1/1000 of an amp.

 

An old tip for this problem -- get your car into pitch darkness one night and see if there is a light anywhere still on, using the principle of the 'light-in-the-fridge'; is it still on when the door is closed? Check boot/trunk, under bonnet/hood, inside everwhere. (mine even has small lamps in the footwells).
Cost's nothing, is easy, quick and needs no brains/experience.
Leedsman.

 

Thanks guts I think we are okay with the car I went out this morning and tested my wifes Concord and get 7.8 milliamps and then tested the jag and get 9.1 milliamps so well with in specs.

Great help...

 

I'm still not sure you are setting up your current testing correctly.

Attached is info including typical quiescent current draws to expect, for anyone interested.

Cheers,

 

Thanks for you input XJRGUY what I was doing was what you had stated. This morning we got THREE multimeters and tryed it using all of them and and all three read 9.1 ma we then used the 1 ohm 10 wat and read mv and all three multimeter read the same once again. So I am at a loss to why Jaguar say the XJ6 should have a 43 ma of battery drain when asleep. If we open the door to put the dome light on all three meters read 3.6 but once that light goes out everything returns to 9.1 ma...

Anythoughts???

 

The best way to reliably measure parasitic draw [quiescent current] is to use a battery disconnect of some sort. Remove a negative cable and insert a disconnect device, then connect your multimeter [set on an ammeter scale] to each side of the disconnect. Be sure the switch on the disconnect is closed and turn the ignition on and make sure everything works normally. Turn the ignition off and remove the key, wait a minute or two to allow all the systems to PROPERLY POWER THEMSELVES DOWN, then open the disconnect. When the disconnect is opened, all the power is now flowing through the ammeter to be measured. The key here is that the systems need to be powered to correctly go to sleep, so to speak. Just sticking an ammeter between a cable and a disconnected battery does not allow that to happen, [in fact, it usually blows the fuse in your meter] consequently your current readings are usually meaningless.

When properly connected, the current measured with a door opened and the interior lights on is about 2800mA or a little above. That's 2.8 amps. After 15-20 minutes it should settle down to about what you see in the document I posted.

You just can't test parasitic draw like you used to 30 years ago.

Good luck!

 

I agree with what you are saying and in my earlier message I did state that with the interior light on I get 2.2 amps, I see you are saying 2.8 amps but that depends on the wattage of the interior bulb.

Thanks for all you input on this matter..

Simprof..