[HugoCountsto7]

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[mweisdorfer]

I think your battery or alternator is going bad. Probably your battery. Bad batteries will make the car go haywire.

[jeddo45]

Originally Posted by DLoBrown

All year I've been struggling with an electrical demon in my 2006 E91 320d. I had trouble starting the car in the winter, and would get the ABS failure warning from the low voltage situation. I replaced the battery in March (registered it with Deep OBD, but I don't think the car has an IBS cable). I've always been able to reset this ABS fault by stopping, turning steering wheel over to the end of range on one side, back to the end of range on the other side and then turning the car off and back on. This weekend I've gotten numerous ABS failure warnings and tried to reset them with mixed success. But yesterday the system went crazy: Multiple alarms going off at the same time, speedometer, tach, fuel economy indicators all going back and forth, no control of the turn signals, windshield wipers turning on and off, engine trying to stall, and a battery warning lamp. Multimeter (and hidden menu) show 13.5 V while engine running. Multimeter at alternator reads 14.11V

We let the car rest over night. Started with no problems this morning. Drove for 45 minutes with no problems. Then suddenly the ABS warning came up. Got it home safely before the crazy show could start again. Still 13.5 V while running and 14.11 V at alternator.

Scanning with Deep OBD for errors:
4A56 Power Management (Currently Active)
4660 Supply Voltage (Not Active, and older)
4A17 Alternator (Not Active, and older)
A few glow plug errors which are not active

It seems like an alternator problem, but I'm always reading around 13.5-13.7 V while running. The problem seems to only start after being on the road for some time. There is no strange sound coming from the pulley system or alternator.

Anybody have experience with such an electrical demon?

Sounds like your alternator could be the culprit. OP check the condition of your battery. If your putting out 14 volts that's too much for a 12 volt battery. If your battery is swelling or bulging at any side that's a sign that your alternator could he having issues.

I'm not completely ruling out the battery. But it does seem strange that your putting out rather high voltage.

[Bob Shiftright]

http://www.e90post.com/forums/showthread.php?t=794502

[GATORB8]

Originally Posted by jeddo45

Sounds like your alternator could be the culprit. OP check the condition of your battery. If your putting out 14 volts that's too much for a 12 volt battery. If your battery is swelling or bulging at any side that's a sign that your alternator could he having issues.

I'm not completely ruling out the battery. But it does seem strange that your putting out rather high voltage.

? 14.4 volts is standard charging voltage across the industry. That's even what car audio components are rated at.

OP are you clearing the codes? can you take a pic of the top of the battery so we can help you confirm the IBS is there?

I think you have an alternator issue.

[VWaddict]

As an electrical engineer, I can say that if you're measuring one voltage at the alternator, and a different voltage at the battery, there MUST be some resistance between the two points... simple Ohm's law.

That said, the voltage drop across the cable (between the alternator and the battery) will be directly proportional to the current flowing through it. (Again, Ohm's law.)

Since no wire can be completely free of resistance, the reading at the alternator output MUST always be higher... and while it's charging the battery there MUST be some current flowing, so there has to be a higher voltage at the alternator (always), it's just a question of how much higher is 'normal'. (And -by inference- how much resistance and current flow is 'normal'.)

Has anybody ever measured THEIR alternator output, to see what it's putting out under the same conditions?

[HugoCountsto7]

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[ctuna]

Germans not stupid enough to put IBS on there own cars?!

[HugoCountsto7]

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[ctuna]

Try putting a slow full charge on the battery see if things change.
Also measuring the resting voltage of the battery in the morning
before first start should tell you something about it's health.

[HugoCountsto7]

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[HugoCountsto7]

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[HugoCountsto7]

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[HugoCountsto7]

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