8 Replies Latest reply: Jul 4, 2013 8:30 AM by FrankOskar
Kris Cawthorn Level 1 (65 points)
Upon start up of the computer I get a message that says "The Apple RAID Card installed in your system requires your attention".
When I open up the RAID Utility I have messages like -

Battery failed (code 0x#0 = 18)
Write cache disabled due to insufficient Battery Charge

Can anyone explain what this means and what I should now do?
Do I need a new Battery and does this mean my RAID 5 isn't saving data correctly?
Thanks in advance for any assistance.

Mac Pro 2 x 3 Ghz Quad-Core Intel Xeon, Mac OS X (10.6.6)
  • Grant Bennet-Alder Level 9 (56,491 points)
    The battery is there to save your data for up to 72 hours in case of a power failure while data is buffered on the RAID card (usually while check blocks are being calculated or checked) before being written to multiple disks.

    Your RAID card will still function, but if the AC power drops, you lose the transfers in progress, with no hope of recovery.

    Contact Apple for a new battery. It may be available as a kit, or you may have to get it sent to the store and bring your card in for a quick swap. Be sure you are talking about the right card -- there are two different ones for the Mac Pro and two different ones for the XServe.
  • Felix Buenemann Level 1 (40 points)
    The controller disabled it's write cache, because without battery backup, I/Os would be lost if the system looses power. Your system will be pretty slow on writes until you replace the battery, but you won't loose any data.
  • Prise2tete Level 1 (0 points)

    Same problem 3 days ago.
    Today and after a first reboot, Battery is good after 20mn of charge.
    I have reboot 2 times more, and now it's good : Battery is OK.

    May be the Battery is deficient, Apple support come this afternoon...

    Sorry for my english, I'm french !
  • Grant Bennet-Alder Level 9 (56,491 points)
    The battery does re-condition itself every few months. It deeply discharges and then re-charges in an attempt to extend overall battery life and eliminate the "memory effect" problem of nickel-cadmium batteries. If you catch it while the battery is discharged and before it has recharged, it will be running with the cache disabled until the charge returns to a high enough level.

    If it stays discharged, it needs to be replaced.
  • The hatter Level 9 (60,930 points)
    FAQ: http://support.apple.com/kb/HT1346


    Question: How often does the battery condition itself?

    Answer: During normal operation, the battery will condition itself approximately every 3 months.

    Question: Why am I receiving a warning "The Apple RAID Card installed in your system requires your attention" after rebooting?

    Answer: If you do not clear out all alerts and warnings in Raid Utility, when the Xserve or Mac Pro reboots there will be a dialog box asking you to clear the warning. When all of the events are cleared, you will no longer receive this dialog on startup.
  • norec Level 1 (0 points)

    I'm getting "Battery failed (other than expired)" error. 

    Does this mean the battery is dead and has to be replaced??


    If so, where is the best place to buy one?

  • FrankOskar Level 1 (0 points)



    I have the same problem too:

    Battery failed (code 0x#0 = 18)

    or in my case, I am german: Die Batterie funktioniert nicht (Code 0x#0 = 18)

    It happened the first time after one year and I replaced the battery. One year later it happened again and I replaced the battery. And one more year later again. This time I decided not to replace the battery.


    I booted the system from the recovery media and started the the raid utility from there and it said: battery charging.


    So I returned to my "normal" partition and it said: battery charging.

    A few days later:  Battery failed (code 0x#0 = 18)


    I repeaded this several times, always with the same result.


    I was quite sure that all the trouble resulted from a firmware bug.


    So I did shut down my Mac, and removed my raid card. On the raid card I disconnected the battery and waited a few minutes and reconnected it. I reassembled all and started my Mac.


    It is running now for more than a month without any further errors.