On boot, iMac Apple logo blinks red after update to Mac OS Sierra

Hello,

I installed Sierra 10.12.1 yesterday and I have the same issue on my iMac 4K 2015 with 2TO Fusion Drive.

I don’t think it’s a hardware problem because I re-installed El Capatin and no issue.

I hope Apple will fix this issue in sierra, for me I’ll wait longtime before to install Sierra again.

Hey Allan:

Brand new iMac (got it last week):

EtreCheck version: 3.1.2 (334)

Report generated 2016-11-29 12:22:22

Download EtreCheck from https://etrecheck.com

Runtime 1:36

Performance: Excellent

Click the [Support] links for help with non-Apple products.

Click the [Details] links for more information about that line.

Problem: Other problem

Description:

Red/Green Apple logo flash on start up

Hardware Information: ⓘ

iMac (Retina 4K, 21.5-inch, Late 2015)

[Technical Specifications] - [User Guide] - [Warranty & Service]

iMac - model: iMac16,2

1 3.1 GHz Intel Core i5 (i5-5675R) CPU: 4-core

8 GB RAM Not upgradeable

BANK 0/DIMM0

4 GB DDR3 1867 MHz ok

BANK 1/DIMM0

4 GB DDR3 1867 MHz ok

Bluetooth: Good - Handoff/Airdrop2 supported

Wireless: en1: 802.11 a/b/g/n/ac

Video Information: ⓘ

Intel Iris Pro Graphics 6200

iMac 4096 x 2304

System Software: ⓘ

macOS Sierra 10.12.1 (16B2555) - Time since boot: less than an hour

Disk Information: ⓘ

APPLE HDD HTS541010A9E662 disk1 : (1 TB) (Rotational)

[Show SMART report]

EFI (disk1s1) <not mounted> : 210 MB

Recovery HD (disk1s3) <not mounted> [Recovery]: 650 MB

Macintosh HD (disk2) / [Startup]: 1.02 TB (809.19 GB free)

Core Storage: disk0s2 23.55 GB Online

Core Storage: disk1s2 999.35 GB Online

APPLE SSD AP0032H disk0 : (24 GB) (Solid State - TRIM: Yes)

EFI (disk0s1) <not mounted> : 315 MB

Boot OS X (disk0s3) <not mounted> : 134 MB

Macintosh HD (disk2) / [Startup]: 1.02 TB (809.19 GB free)

Core Storage: disk0s2 23.55 GB Online

Core Storage: disk1s2 999.35 GB Online

USB Information: ⓘ

Broadcom Corp. Bluetooth USB Host Controller

Apple Inc. FaceTime HD Camera (Built-in)

Thunderbolt Information: ⓘ

Apple Inc. thunderbolt_bus

Configuration files: ⓘ

/etc/hosts - Count: 1

Gatekeeper: ⓘ

Mac App Store and identified developers

System Launch Agents: ⓘ

[not loaded] 7 Apple tasks

[loaded] 170 Apple tasks

[running] 94 Apple tasks

System Launch Daemons: ⓘ

[not loaded] 41 Apple tasks

[loaded] 161 Apple tasks

[running] 100 Apple tasks

User Launch Agents: ⓘ

[loaded] com.google.keystone.agent.plist (2016-11-25) [Support]

User Login Items: ⓘ

Arq Agent Application (/Applications/Arq.app/Contents/Library/LoginItems/Arq Agent.app)

Alfred Application (/Applications/Alfred.app)

Divvy Application (/Applications/Divvy.app)

Dropbox Application (/Applications/Dropbox.app)

TextExpander Application Hidden (/Applications/TextExpander.app)

Internet Plug-ins: ⓘ

QuickTime Plugin: 7.7.3 (2016-11-23)

3rd Party Preference Panes: ⓘ

None

Time Machine: ⓘ

Time Machine not configured!

Top Processes by CPU: ⓘ

4% fontd

2% WindowServer

1% kernel_task

0% com.apple.AmbientDisplayAgent

0% logd

Top Processes by Memory: ⓘ

1016 MB com.apple.WebKit.WebContent(3)

681 MB kernel_task

451 MB MTLCompilerService(16)

377 MB Polymail

328 MB WindowServer

Virtual Memory Information: ⓘ

3.05 GB Available RAM

60 MB Free RAM

4.95 GB Used RAM

2.99 GB Cached files

0 B Swap Used

Diagnostics Information: ⓘ

Nov 29, 2016, 11:47:46 AM Self test - passed

A Safe Mode boot deletes system caches that can help after an update or upgrade.

Follow these steps to start up into safe mode.

1. Start or restart your Mac.
2. Immediately after you hear the startup sound, press and hold the Shift key.
3. Release the Shift key when you see the Apple logo appear on the screen.

After the Apple logo appears, it might take longer than usual to reach the login screen or your desktop. This is because your Mac performs a directory check of your startup disk as part of safe mode.

To leave safe mode, restart your computer without pressing any keys during startup.

Same problem, after several calls to Apple they were not aware of this. Tried several re-installs etc and tried usual repairs, removed virus checker and pruned Little Snitch. No significant issues as yet but red box still appears. Time Machine slow and slight problem with mail but neither show stoppers.

Apple suggested I take to Repair as issue does not show on Booting from El Cap on attached disk and first level support suspected damaged disk. S.M.A.R.T. checks show disk ok. I suspect some bug that will be fixed on next update.

I had/have this problem too with a mid 2015 iMac retina running Sierra. I worked with level 2 to no avail. I sent him a slo-mo video of the flash just to prove that I wasn't hallucinating. Otherwise it's running fine with the exception of some apps aborting when quitting. The Level 2 said he was forwarding my video to Engineering to see what they think is wrong. That was two weeks ago.

Some programmer in Apple dropped into some condition where he/she use the "red flash" to signify that they are in a situation that they should never be in but just in case they get there flash the logo red.

Got the same issue after update to Sierra, Got a imac 21 inch retina late 2015 model. only 3 months in the house.

Barely used, no extras.

100% sure its linked to the Sierra upgrade.

In addition have noticed some graphics bugs, nothing mayor but still...

Same problem, after several calls to Apple they were not aware of this. Tried several re-installs etc and tried usual repairs, removed virus checker and pruned Little Snitch. No significant issues as yet but red box still appears. Time Machine slow and slight problem with mail but neither show stoppers.

Apple suggested I take to Repair as issue does not show on Booting from El Cap on attached disk and first level support suspected damaged disk. S.M.A.R.T. checks show disk ok. I suspect some bug that will be fixed on next update.

Finally upped to Apple second level support after I found that starting in safe mode eliminated the red box flash, and had a long discussion and help from a very knowledgeable support person. Tried eliminating dozens of extensions, startup items etc and many restarts none of which eliminated the issue of the red box. Notably did not eliminate any Apple extensions. So suggest that problem is a bug in an Apple extension that is immobilized with a safe boot.

Thanks Mike. Apple surround turning RED IS WELL DOCUMENTED. I also have at shut down a missing PROGRESS SPINNING WHEEL. Hard to tell if the computer is shut down. Also discovered, FREQUENTLY VISITED FAVOURITES will not show up at all. CAPTURE DATA WAS PLACED ON MY COMPUTER AND SENT TO APPLE for them to correct the software problem. Since dealing with APPLE I have yet to experience this product to run without issues. Dear APPLE ENGINEERS.... Create, Test then Share. It is now up to Apple.

Here too on new iMac 21.5, 4K retina, late 2015 but NOT on mid 2012 MBP. Both updated from El Capitan to Sierra at about same time - both basic set up, no "special"apps! The start up in safe mode seems to have stopped it this time.

Something a little different...spent a few hours with apple supprt on the phone and the conclusion was faulty hardware on the iMac 4K. This is a recent purchase for me and they advised to return. We tried resetting the ram, repairing the disk, and then ultimately a wipe and clean install of OS Sierra. None of which resolved the issue. Disappointing because I pay the Apple price premium because they usually work really well...