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Discussion Starter #1
Hi

Had a bad battery. Was an exide 95ah agm. 3 seperate independents tested it and advised to replace. Replaced it with a new varta 95ah agm. The garage guy registered and installed it.

Im not getting any errors discharge or drain but im monitoring my voltage and its dropping 0.1 a day. Yesterday i drove around 2hrs highway.
Today morning it was 12.5. Later at night it was 12.4. Testing using a ring smart charger. Same reading under the hood or direct at battery. Starter motor test shows 10v.

Im assuming my draw is less than 80ma when its a sleep as im not getting high drain errors.

Ive invested in a solar power trickle obd charger. Its an AA brand 2.8w. Im not sure how much that will help maintain the battery at such low power. I plug it into the obd and leave on dash in the hope that it maintains or tops up some of the sleep mode drain.

Ive read under 12.4vcan damage the battery long term. I will hit under 12.4 with 2/3 days parked for sure. I drive it mostly 3/4 times a week. Could be 60 mile runs or even a single 200 mile run a week.

Id like to see what my current batt draw is when its locked. Ive read 20ma is about norm.

How can i test this without having to disconnect the battery or without running the power meter in series?

Is there anything like a MA DC monitor i can clip on to the battery without disconnecting it first?

Is there any software that will read the data from the car itself? The car stores temp. Voltage and general state of health charge. Does it also store current whilst its asleep?

Ive looked into ma dc clamp meters but again ive read the cheaper ones are not accurate.

Ive read not to disconnect battery and not to pull fuses so really looking for either software or hardware to be able to check what the car baterry current draw is at rest/sleep mode locked?

After market stuff installed

Headrest dvds x2.
Tv receiver
Rear taillight led bar upgrade
Front ring lights upgraded so they white instead of yellow.

Any help advice on how i can read the current draw would be appreciated.

Thank you
 

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Discussion Starter #2
I had a go at trying to check my current draw from the battery using a multi meter. I kind of by watching and educating myself via YT and forums. I thought I nailed it but i miserably failed.

here goes

double clicked the boot locking mechanism to try show as closed.

the multi meter i set to mA and connected the red probe to the 10A side.

the keys are not in the dash. so everything off.

i disconnected the negative from the battery.

connected the multi meter in series with the battery.

i was getting a reading of about 70mA. after a few seconds it started to decrease as low a 10mA but then after about a minute or two the reading starts to bounce around and all the digits just go crazy. why is that? i tried it twice and same again. get a reading starting from 90/ 80mA and creeps lower.then it starts dancing again.

I also tried by leaving the meter connected. closing the trunk and locking the car and hoping i can read the multi meter through the glass window when i lock the car. as soon as i locked the car. the meter reading went to zero and the car would not open. I had to open the car with the key and reconnect the battery from inside the car and then open the doors. not sure what i did wrong there.

im not a car elecy and only know very little basics just from a little reading here and watching a few videos.

I was trying to see battery current draw when the x5 is fully in sleep mode.

could anyone please possibly point me in the right direction?

will it work if i connect the multi meter in series. close the trunk and NOT lock the car. just allow the car to enter sleep mode - (8-9 mins) and see if it still shows the current draw?

apologies for asking totally noob questions.. sorry
 

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Discussion Starter #3
I sat in the car and just took the key out just to see what happens.

It took about a minute for the P light to go off the gear shifter.

2/3 mins and some buzzing noise from nr the centre front. Could be sat nav. I have no cds in the car so im assuming sat nav cd. The noise lasts around 15 secs.

After about 7/8 mins the driver door window lock light comes on. On the cluster the red P light comes on. Looks like its getting ready to shut down.

Another minute or so and them lights switch off.

No more sounds or anything visual.

I read a document that said it takea 8mins for x5 to sleep without locking. Goea to sleep straightaway if locked.

When locking the car with a key remote, the red light flashes under rear view mirror. This didnt flast even after 16mins plus.

So i thought i ll get in the car. Put my passenger seats down and connect the meter to the negative terminal. I put meter to the 500mA setting and reading mA DC.

I got a reading of 3.2 mAand none of the things happened with the meter connected.

I was hoping after 10mins or so. The car would have cycled through all the above stages and then id have a reading of current draw. Key out but not locked. But nope. Reading was 3.2 for at least 18mins or so.

Ordered a used Fluke 355 clamp meter. Its pretty cheap 160 quid. UK its still £500 plus. I ll be able to resell it after ive played around with it at that price.


Will update what current draw readings i can pick up off from the Fluke when I receive it.

On a side note. Before experimenting with the x5 e70. I had a play on a 2001 nissan micra. Just to see what happens. With the ignition off. Just the bonnet open. The micra current initially is around 80mA then slowly drops and bounces to 16mA.

On the x5 its like it knows ive got a meter connected and it doesnt want to play ball.

Im going to try a voltage drop across the fuses too but first id like to see my current draw from the battery.

To be continued.
 

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Nuclear engineer
02/2012 X5 35d M57Y CPO 100K miles NOKIAN WR G3 20K miles
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19,395 Posts
A battery sitting on the bench self-discharges through its internal resistance. Understand at least Wikipedia level battery physics and technology.

A meter is worse than useless without understanding.

Take your BMW to the BMW Service Center and pay them to cure your problem. Don’t tell them how. Don’t ask stupid questions. Pay.
 
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@Doug Huffman.

Came across a lot of your posts. Some golden advice. Most of the useful info came from your posts. Some goes over my head but still a really good read. Thank you for your time and sharing the information. Gives guys like me at least some where to start. Respect to you.
 

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Hi

Had a bad battery. Was an exide 95ah agm. 3 seperate independents tested it and advised to replace. Replaced it with a new varta 95ah agm. The garage guy registered and installed it.

Im not getting any errors discharge or drain but im monitoring my voltage and its dropping 0.1 a day. Yesterday i drove around 2hrs highway.
Today morning it was 12.5. Later at night it was 12.4. Testing using a ring smart charger. Same reading under the hood or direct at battery. Starter motor test shows 10v.

Im assuming my draw is less than 80ma when its a sleep as im not getting high drain errors.

Ive invested in a solar power trickle obd charger. Its an AA brand 2.8w. Im not sure how much that will help maintain the battery at such low power. I plug it into the obd and leave on dash in the hope that it maintains or tops up some of the sleep mode drain.

Ive read under 12.4vcan damage the battery long term. I will hit under 12.4 with 2/3 days parked for sure. I drive it mostly 3/4 times a week. Could be 60 mile runs or even a single 200 mile run a week.

Id like to see what my current batt draw is when its locked. Ive read 20ma is about norm.

How can i test this without having to disconnect the battery or without running the power meter in series?

Is there anything like a MA DC monitor i can clip on to the battery without disconnecting it first?

Is there any software that will read the data from the car itself? The car stores temp. Voltage and general state of health charge. Does it also store current whilst its asleep?

Ive looked into ma dc clamp meters but again ive read the cheaper ones are not accurate.

Ive read not to disconnect battery and not to pull fuses so really looking for either software or hardware to be able to check what the car baterry current draw is at rest/sleep mode locked?

After market stuff installed

Headrest dvds x2.
Tv receiver
Rear taillight led bar upgrade
Front ring lights upgraded so they white instead of yellow.

Any help advice on how i can read the current draw would be appreciated.

Thank you
I today searched for parasitic draw and found out that car fuse 75 (20A) draw is 1,3 mV when car is locked and sleep. Someone has replaced fuse75 what supposed to be 5A to 20A, since i installed new xtrons unit in my car i removed that fuse (xtrons still working without fuse) and will see if parasitic draw is fixed.
What i did is, i went inside car, locked doors, waited til car went to sleep and the hunt for draw began with multimeter. All other fuses had 0.0 mV and the fuse 75 in trunk was chewing my battery drawed huge amount of amps.
Every morning i had hard to start car and xtrons showed 10,7V in morning after car sitting 10h with full battery. and when i hit starter it goes 8.6V

if car hasnt been started 2 days battery is so flat that interior lights dont work.
 

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Discussion Starter #7
I today searched for parasitic draw and found out that car fuse 75 (20A) draw is 1,3 mV when car is locked and sleep. Someone has replaced fuse75 what supposed to be 5A to 20A, since i installed new xtrons unit in my car i removed that fuse (xtrons still working without fuse) and will see if parasitic draw is fixed.
What i did is, i went inside car, locked doors, waited til car went to sleep and the hunt for draw began with multimeter. All other fuses had 0.0 mV and the fuse 75 in trunk was chewing my battery drawed huge amount of amps.
Every morning i had hard to start car and xtrons showed 10,7V in morning after car sitting 10h with full battery. and when i hit starter it goes 8.6V

if car hasnt been started 2 days battery is so flat that interior lights dont work.
Just googled Xtrons Unit. Looks really good. Was it easy enough to install? Does the xtron unit also show you battery voltage?

I didnt lock the doors whilst inside the car. I thought the alarm will start going off. I ll try what you did and do the voltage drop test and see what i find.

Hope your problems fixed and thank you for sharing what you did.
 

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Discussion Starter #8
Got hold of a couple clamp meters.

My X5 e70. If i stay in car. Lock the car with remote pressing lock button twice to disable interior alarm/tilt. I get about 800ma to 1amp draw for about 10mins. Another 10mins around 500mA draw. It takes 20mins or so and it will drop to 180mA. I for sure have a problem. I get no battery drain errors. Battery is brand new. AGM 95ah varta. The amp clamp is showing most of the drain on
1028517
the blue line ive highlighted in the picture attached.

I did a current draw test same key locked alarm disabled on an x5 e70. Brother in laws. For about 5mins his current was around 1amp. After 5mins. His reads 0.00. Should be 0.02 but i was getting. 0.00. Within 5mins full shut down and sleep mode.

Mine 20mins and then still draws 160 -180ma. That will remain for as long as 70mins.



Im going to try fuses when i get chance. To narrow down further.

I know of the trunk fuses and the fuses under the glove. I read about some difficult to get to fuses nr the glove box?

I may try a friend who has a diagnostic tool see if theres anything showing.

20210411_001045.jpg
 

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Discussion Starter #9
Done a continuity test / voltage test on all the trunk fuses and as many fuses i could reach under the glove fuse box. I couldnt get to the fuses at the far back.

A friend has launch diagnostic software. It picked up a rear interior light error which ive already pulled out as its a blown bulb. Some kind of steering wheel angle error. That was it.

Battery registration may have been wrong. I have a cigarette lighter battery voltage reader. Ive tested to compare reading direct from battery and its always been correct. Last two weeks since new battery. AGM. I was pretty much getting a steady 14.X reading while driving. Yesterday selected AGM using launch. Now the voltage while driving is typically low. In the 12.Xs. if i put headlights on. It jumps to 14.0. Or sometimes goes higher when the brakes are pressed whilst driving. When its idle it will show 14.0. But when driving mostly 12.2V.

Once a week im giving battery a full charge via external AGM charger front bonnet terminals.

Im not making progress so car booked in with BMW dealer. See what their diagnostic shows.
 

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Discussion Starter #10
Error codes using a friends Launch diagnostic system OBD health scan.



Transmission Control Module.

CF37 message from car access system to body bus faulty receiver EGS Transmitter car access system.

VTG transfer case

55D0 message (steering wheel angle, 0xC4) error, receiver VTG, Transmitter DSC.
 

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Dropped car off with BMW Dealers. Told them to cap diagnosis time to 2hrs. £118 per hour.

They have had car all day and still doing further diagnosis. They keeping car for another day.

The vehicle had a tracker. I did not know it had a tracker. That was drawing current. They have disconnected it.

Two radio ariels. These could be the tv tuner ariels not sure. They were drawing current. Now been disconnected. They looking further into the radio.

They did say I may not need extra work but I wont know till they have completed or done as much as they can.

Will provide another update when I get it back.
 
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