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Discussion Starter · #1 ·
ANybody care to do me a favor and go test the voltage output at the battery when the car is running? i think my VR is on the way out...

im seeing a steady 14.8 volts when running, and it fluctuates a tad every once and a while down to 13 and change and back up to 14.8..

I get random IDrive warnings for EVEYRHITNG from reduced engine power to edc/dsc/start off assistance errors etc.

I need to see what the voltage output on this car stock should be
 

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ANybody care to do me a favor and go test the voltage output at the battery when the car is running? i think my VR is on the way out...

im seeing a steady 14.8 volts when running, and it fluctuates a tad every once and a while down to 13 and change and back up to 14.8..

I get random IDrive warnings for EVEYRHITNG from reduced engine power to edc/dsc/start off assistance errors etc.

I need to see what the voltage output on this car stock should be

14.2-14.5 right after start up. 12.8-13.3 normally when car has settled in and running normally. 11.8-12.2 when shut off and just reading battery. Never had any battery issues. Hope this helps
 

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Discussion Starter · #3 ·
So if mine is living in the 14.8 + range... its time for a new alternator (dont want to deal with changing just the VR)
 

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So if mine is living in the 14.8 + range... its time for a new alternator (dont want to deal with changing just the VR)

Yeah I would say so. That is definetly not normal. It is cooking your battery. The only way I could see it being that high all the time is if the battery was not holding a charge, and the alternator is getting weak battery feedback. In any event you will probably need a battery. I would try that first since it is the cheapest route. Get a battery, and see if voltage output goes down as car warms up. If so you would have saved a lot of money. :)
 

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Discussion Starter · #5 ·
i put a brand new battery in last night, it still sticks at 14.8... but its more steady at 14.8

got the same errors this morning on cold startup...

let it idle and then restart and they went away
 

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i put a brand new battery in last night, it still sticks at 14.8... but its more steady at 14.8

got the same errors this morning on cold startup...

let it idle and then restart and they went away

Okay if it is staying at 14.8 that means it is a problem with the alternator/voltage regulator. 14.8 should only be seen right after start up for a few minutes.
 

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Mine starts at around 13 but goes up to 14.8 and when its really cold like below freezing it hits 15-15.1. At least that's what my Escort Redline tells me off the cigarette lighter.
 

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Dealer just replaced the battery last Friday. Going home the voltage was running 11.2-13.5.

The next day the voltage was around 11.00-11.40 for about 25 minutes of driving (about 25 miles). It then moved up to 12.5-13.5 for the last 5 minutes driving.

Three hours later, it prompted with the famous "increased discharge". The next driving home was around 12.5-13.9. Could it be Voltage Regulator or Alternator?

Thanks in advance!
 

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Your VR is dieing. As others have said 13.8 to 14.1 is what you should see. My radar detector displays voltage and I see 13.8 most of the time and 14.1 directly after startup.
 

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Dealer just replaced the battery last Friday. Going home the voltage was running 11.2-13.5.

The next day the voltage was around 11.00-11.40 for about 25 minutes of driving (about 25 miles). It then moved up to 12.5-13.5 for the last 5 minutes driving.

Three hours later, it prompted with the famous "increased discharge". The next driving home was around 12.5-13.9. Could it be Voltage Regulator or Alternator?

Thanks in advance!
Nicko.... I had similar symptoms and was getting worse to the point where It became dangerous to drive - one component at a time was failing. Under heavy load.. I was getting spikes between 8v and 17volts!

I replaced both battery (was overdue) and also the Voltage Regulator about 2-3 weeks ago and the beast is back!
The replacement is actually very simple - there is a great DIY here.

Terry
ANybody care to do me a favor and go test the voltage output at the battery when the car is running? i think my VR is on the way out...

im seeing a steady 14.8 volts when running, and it fluctuates a tad every once and a while down to 13 and change and back up to 14.8..

I get random IDrive warnings for EVEYRHITNG from reduced engine power to edc/dsc/start off assistance errors etc.

I need to see what the voltage output on this car stock should be

Sent from my Nexus 5 using Tapatalk
 

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The alternator should last few-several years more. The famous battery drainage issue forced the alternator to work overtime.
From now on I will always use the battery tender when parked.
 

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I would argue that substandard quality control caused the failure. The alternator in an E60 works only when told to by the DME / IBS unlike every other car made before the introduction of these battery management schemes. Those alternators put out max voltage all the time.

If we were to go in and actually determine mode of failure for these regulators, my money would be on the BSD control arrangement or the variable output stage.
 

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A battery tender (unless weeks at a time) is a funny bandaid for a near $100K car.


I will pick up a cigarette lighter monitor to use for trouble shooting next time (likely on another 50,000 miles!) Thanks.
 

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I would argue that substandard quality control caused the failure. The alternator in an E60 works only when told to by the DME / IBS unlike every other car made before the introduction of these battery management schemes. Those alternators put out max voltage all the time.

If we were to go in and actually determine mode of failure for these regulators, my money would be on the BSD control arrangement or the variable output stage.
You are right Jcolley! The voltage reading is 14+ after the battery was fully charge by battery tender.

I wish they would be using "all" Japanese electronic-electric parts. The Japanese has perfected this area since the birth of gaming industry.
 
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