P38A Electrickery drain,where am I going wrong?

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I had a 250ma drain on my L322 and it flattened the battery in 3-4 days. A clamp meter and a multimeter found about half the drain, which was the mobile phone module. I have yet to find the rest cos it is much better now and I gave up looking. Might start again in the spring, but it's not too difficult to find once you get going.
 
Cheers Ant, I'm trying to think of everything that stays live and draws power with the ignition off.. my r/f cannot be activated by spurious signals due to @brianp38dse 's second fob work around. All I can think of is the clock and the becm. We could do with a dummies "how to guide for drain detection" any takers? @martyuk ?
Just as an aside (I too use the 2nd fob for the rf receiver) but have you checked that the LED at the side of the gear selector has completely extinguished (BECM gone to sleep)? Nice and easy on these dark nights...
 
Just as an aside (I too use the 2nd fob for the rf receiver) but have you checked that the LED at the side of the gear selector has completely extinguished (BECM gone to sleep)? Nice and easy on these dark nights...

Bit of a problem with that as Alan has a manual same as me and there is no light:( which makes it a bit harder to tell if becm is sleeping.
 
Just as an aside (I too use the 2nd fob for the rf receiver) but have you checked that the LED at the side of the gear selector has completely extinguished (BECM gone to sleep)? Nice and easy on these dark nights...
I thought there were 2 states for the LED's "Barely glowing"=BeCM asleep and "Clearly alight" = BeCM awake. But maybe I have that wrong.
I will check what I have read previously.
 
It doesn't work like that.
If, as you say there is 0.5A being drawn by other things on the car and you add in a 5w lamp then yes, it will illuminate. However the total current being drawn from the battery will be very slightly less because the lamp is a higher resistance than the earth cable.
All that will happen is that the lamp will become one half of a potential divider.(with the rest of the cars circuits being the other half)
However if you tried the same experiment with a 55w lamp on a car drawing 0.5A it probably wouldn't illuminate at all. (it might glow slightly)
The total current flowing in the circuit will go less as you add more lamps because the resistance will go up.
I'm not in any way trying to belittle anyone, just trying to explain that a lamp in the circuit really doesn't work for the reasons above.
Yes, I didnt account for resistance I guess......as I said, I am not a leccy man....many thanks for clarifying.
 
Still waiting for the patch leads, bloody Royal Mail. Round I live on doesn't have a dedicated delivery person, we only get post if anyone who has finished their round wants overtime.:mad:. The car started yesterday and I used it all day without a problem by the way. From other posts it looks like I'm not the only one with this fault.:(
 
What a a way to run a business lol only get post I’ve overtime’s required and I think ur right regarding the battery drain I think I’ve been lucky so far in that respect and I’ve still got the old type reciver in the boot
 
Still waiting for the patch leads, bloody Royal Mail. Round I live on doesn't have a dedicated delivery person, we only get post if anyone who has finished their round wants overtime.:mad:. The car started yesterday and I used it all day without a problem by the way. From other posts it looks like I'm not the only one with this fault.:(
Aye, it used to be run as a "Service" and not for a profit. Now it has shareholders to pay and not customers to SERVE.
 
Well, I ventured out to the garage today and took the charger off and disconnected the battery. Connected the multimeter between the earth strap and the -'ve terminal. Put a spare bonnet catch in the o/s bonnet lock.Locked the car and waited for a couple of minutes for the becm to go to sleep and the meter showed a reading of 0.87 amps. I pulled every fuse and relay and the reading stayed the same. I also pulled the eas relay. Reconnected the battery and disconnected the r/f and second fob receivers, I'll see what happens tomorrow.
 

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your multi meter is set on AC current range not DC range so that figure is incorrect does it not have a DC current range you would get the true drain using or loaning a old Avo-mk 8 analogue multi meter less small electronics components to be affected by the outside Temperature and means of manual calibration
 
Hi Alan

That's a chunky current. It looks like you have the meter set to read AC Amps (~A). Is that the right setting on your meter for reading DC Amps?

I have a feeling the becm would take a lot longer than a couple of minutes to go to sleep - someone else may be able to comment on how long.

My old Subaru Impreza had a current drain - that turned out to be a faulty tracker which was hard-wired in to the battery via its own in-line fuse. Do you have any accessories which might be the culprit?

Pete
 
Happened to mine years ago when 1st brought it dealer said he had same problem when left for few days mine was self levelling all week why I was working away
 
Happened to mine years ago when 1st brought it dealer said he had same problem when left for few days mine was self levelling all week why I was working away
Thought of that Pete, I pulled the eas relay, ta.Don't need the RR at the moment as I'm not driving, the chauffeuress likes her X type.:eek: I'll have another look when the weather improves.;)
 
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