Battery Drain

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Whisky Mac

New Member
Posts
9
Location
Moray
As this is my first post I apologise if you feel this has been flogged to death before.
My car is a range rover l322 4.4 v8 auto 2003 with LPG dual fuel.
There is definitely some electrical issue.
I have done a test on the battery voltage is good 12.6v after recharging. Alternator is returning 14v at 2000rpm with lights and full beam on.
I have replaced FSR, disconnected the audio equipment and have pulled fuse 12 as the small fan on the central control panel was continually running.
I have also tested mv over the fuses all returned no current draw. The ECU light at the gear lever had gone out when I used the multimeter.

However the car keeps waking up hence the reason for now pulling fuse 12.
Sat in the car this evening for 45min the ECU was still awake. In that time the light switch flashed several times and there appeared to be a relay activating within the dash behind this switch.

As far as I can see everything is of no lights on in the boot, internal lights out.

At a bit of a loss as to what to do next, any help appreciated.
Thanks
 
Sorry should have mentioned the car has had a facelift, so the headlight wipers have been removed. Thanks for your comment.
 
Had a similar problem, alternator output spot on, but still drain on battery. It was the" rectifier" on the alt. I used the multimeter, it showed a current draw, while no lights etc. were in use. Are sure the battery is OK ?
 
I'm going to take the car for a 40mile trip to see how the alternator performs and see how the battery is tonight and in the morning. What was the test you did with the multimeter reference the rectified?
 
I'm going to take the car for a 40mile trip to see how the alternator performs and see how the battery is tonight and in the morning. What was the test you did with the multimeter reference the rectified?
You have to put your meter in series, disconnect a battery lead and set meter to read amps . By disconnecting fuses one at a time you will find where the current draw is. I think your voltage reading's are not great but, OK.
 
So do you think my problem lies with the battery / alternator?
That is certainly a possibility. A 40 mile trip will not fully charge the battery.
Buy yourself a cheap DC clamp meter, put it round the battery negative lead, no need to disconnect the battery, it will tell you what the current drain is, then you can disconnect the alternator and see if the drain reduces. After that as suggested by KB22 you can pull fuses.
You should see 14.5 to 14.7 volts out of the alternator and a fully charged better half an hour after removing a charger should show 12.8 volts or a little more.
 
You have to put your meter in series, disconnect a battery lead and set meter to read amps . By disconnecting fuses one at a time you will find where the current draw is. I think your voltage reading's are not great but, OK.
Thanks for the response will try.
 
That is certainly a possibility. A 40 mile trip will not fully charge the battery.
Buy yourself a cheap DC clamp meter, put it round the battery negative lead, no need to disconnect the battery, it will tell you what the current drain is, then you can disconnect the alternator and see if the drain reduces. After that as suggested by KB22 you can pull fuses.
You should see 14.5 to 14.7 volts out of the alternator and a fully charged better half an hour after removing a charger should show 12.8 volts or a little more.
Great thanks for the advice, I will look into check this out.
 
That is certainly a possibility. A 40 mile trip will not fully charge the battery.
Buy yourself a cheap DC clamp meter, put it round the battery negative lead, no need to disconnect the battery, it will tell you what the current drain is, then you can disconnect the alternator and see if the drain reduces. After that as suggested by KB22 you can pull fuses.
You should see 14.5 to 14.7 volts out of the alternator and a fully charged better half an hour after removing a charger should show 12.8 volts or a little more.
Hi Datatek, I have looked for a cheap DC clamp meter,with no luck. The ones on offer are AC/DC volt. but only AC current. Do you know of any to fit the bill?
 
I bought one of these from Amazon last year. Amazon product
Definitely does DC Current, and great for checking battery drain.

Remember L322 takes much longer than P38 to fully go to sleep mode. Was about 10 mins on the one I worked on.

Leave drivers window open so you can reach switches, etc without opening the door, and bypass the bonnet switch (also a common cause of BCM wake-up). After the BCM sleeps you can probe around with the clamp meter, starting with battery terminals. Then move to alternator wiring, etc.
 
I bought one of these from Amazon last year. Amazon product
Definitely does DC Current, and great for checking battery drain.

Remember L322 takes much longer than P38 to fully go to sleep mode. Was about 10 mins on the one I worked on.

Leave drivers window open so you can reach switches, etc without opening the door, and bypass the bonnet switch (also a common cause of BCM wake-up). After the BCM sleeps you can probe around with the clamp meter, starting with battery terminals. Then move to alternator wiring, etc.

Cheaper from CPC I think:D
 
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