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Discussion Starter #1
Just want to see what you guys voltage readings are from test 9 unlocked from the cluster. This morning i just unlocked mine in my 99 540i and with the key in position 1 it fluctuates between 12.1v and 12.2v and running im getting 13.8v. But when i use my volt meter at the battery posts key off 12.6v-running 14.4-14.5. If you guys who have unlocked your cluster can post your readings car off key postion 1 and running would help alot. Oh by the way im still using the red autozone dl-49 i purchased almost 5yrs ago.
 

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Just call me 777.
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You have a bad battery. My car does the exact same because I killed the battery when my alternator died.
 

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Wingnut
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there usually is a difference between the cluster voltage reading and reading with a dvw at the battery posts, the cluster reads a bit lower due to wire lengths, gauge and imperfect connections. there was a discussion once about this here. and the common determination was .if going by the cluster reading, establish your car's norm and look for variances in it if problems arise.
 

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Also...when doing TEST 9 with ignition in KL R...there's battery drain since many control modules are running...thus the reading will change.
 

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Car has not been used for a week, I get 12.3-12.4 volts in the cluster test when car is off so battery is about 75% charged. Battery is tested ok. Dont have any problems but the E39 has always been very sensitive to battery voltage and when measuring you often gets scared that it is too low.
http://www.bimmerfest.com/forums/showthread.php?p=5747151
 

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Wingnut
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reading the voltage at the battery, 12.6 or so is fully charged. if you were to read your voltage at the batt terminals, and it is 12.6vdc, then read your cluster voltage, remember this number. this is your fully charged number..
 

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Have you verified the accuracy of your DMM?
 

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Wingnut
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edjack raises a good question. short of visiting a PMEL lab, reading a couple of new 9 volt batteries will give you an idea. or another voltage batteries.
 

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Discussion Starter #9 (Edited)
Have you verified the accuracy of your DMM?
I am using a harbor freight dmm which is probably not the most accurate. Also that voltage i posted is from sitting for about a week no alarm set-so im guessing everything is ok cause the car starts strong without hesitation. I just wanted to compare with the other festers since i'm new to this unlocked cluster thing.
 

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I wouldn't be worried with those readings. So long as its around 14V when the engine is running then its charging the battery, so all good. If it was 12V with the engine running I'd be worried.

Spod
 

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Wingnut
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just to say, i have a harbor freight dmm as a backup one and have found it to be very accurate for these kinds of things, its the full size one, not the small red one.
 

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ALGhoul
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Just want to see what you guys voltage readings are from test 9 unlocked from the cluster. This morning i just unlocked mine in my 99 540i and with the key in position 1 it fluctuates between 12.1v and 12.2v and running im getting 13.8v. But when i use my volt meter at the battery posts key off 12.6v-running 14.4-14.5. If you guys who have unlocked your cluster can post your readings car off key postion 1 and running would help alot. Oh by the way im still using the red autozone dl-49 i purchased almost 5yrs ago.
You are right it's not accurate
What I mean bmw cluster for test 9
I trust my voltmeter tried 3 types cheap and expensive all give same result since that day when I check voltage Iam not using test 9 which is a crap
 
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