Is 13.5-13.7volts too low
 

Hey all. Trying to diagnose a battery/charging issue.

When I run test 9, it is showing 11.6.volts or so (I know that is low) just wondering if my issue is just the battery or is caused by a bad alternator.

When running the vehicle the volts sit at 13.5-13.7 (pretty much 13.7 most of the time). I thought it should sit between 14.2-14.7volts, however I watched some videos of people replacing their alternators and it brought their volts to 13.5ish...

Thanks for the help.

(Battery is about 5years old...I realize I need a new one, but I don't want to put a new battery into a bad alternator)

Merry Christmas (I am thankful for automotive forums)

That looks fine if its above 13.5 - I had my alternator done this year and battery replaced last year and I hover from 13.5 to 13.8 or so, mostly 13.8 - in the months leading up to my alternator failure I was hovering around 13.1 - 13.2v while driving -

Phew, great news, thanks!

I would definitely probably replace the battery though - that voltage when not on after sitting for a while is low

I don't know if all X5 (E53) are like this but when my OBC Test #9 shows 13.8v the jump terminals under the hood reads 14.2v (with a Fluke VM). Seems the OBC Test #9 reads a little on the low side. This is with the car at idle. Doesn't seem to change much at higher revs or with (electrical) load.

If you are seeing 13.5v and above, it sounds like your alternator is all good.

Nothing beats a real Professional Fluke meter! The reading on the dash are a processed reading at the module. ALWAYS use a Fluke or other quality DVM to get accurate information!

Battery replaced, thanks!

Good to know, didn't think about testing at the jumper points. New battery and ctek 7002 ready to go.

I am think due to me lack of long drives (about 2-3miles per day) and lack of frequency driving the X, the ctek should help out.

Thanks again!

Your short drives will NOT allow the battery to come up to full charge ever. A trickle charger will resolve the issue and allow the battery to have a LONG full life if used frequently. Recommendation would be weekly if you can not do daily.

Also be aware that the engine will never reach operational temps, so frequent oil changes (when engine is HOT) will allow some of the condensation to be removed. However, the build up of condensation in even colder temps will be an issue to keep in mind. See Oil separator issues all over the forum. The 4.4 are on the back of the intake, PITA.

:iagree: