HP Elitebook Caps Lock blinks erratically, (17, 16, 12 times etc), screen never comes on (8770W)

Question

Who has detailed repair information?

I had to replace the motherboard after the old one failed to turn on completely.

I've learned that the separate laptop components are all required (modem, mezzanine boards for audio and USB, etc) for this laptop to do anything at all - if I don't, the power light comes on and the fan spins, nothing else.

With everything connected (battery, HDD do not make a difference), this is what happens: the Caps Lock light blinks a few times, then flashes rapidly or turns off for a second, and the sequence repeats.

The number of blinks varies, but never matches any of the codes listed here:

HP Notebook PCs - Computer Does Not Start and Emits an LED or Beep Code

The screen backlight never turns on, and there's never any VGA or DisplayPort output either.

Edit: Win-V or something else while restarting did something to the laptop. As opposed to 1 blink per second, it now slowly blinks Caps Lock AND Num Lock 5 times total (Num Lock would not blink at all before), about 2 seconds per blink. According to HP (see link above), this means "General system board failure".

Solution

First, remove and reseat the memory modules to make sure they are well connected.

Try a BIOS reset on this circa-2011 design with the HP BIOS Update routine:

Do Win-B and keep holding them down while you press-and-hold the power button for 3 seconds. Let go of the the Power button while still holding Win-B. If the Power light goes out, repeat with only 2 seconds press-and-hold of the power button.

If that does not bring up the HP BIOS Update, then repeat the above with Win-V instead.

Since you report this results in five flashes, HP's troubleshooting web page section titled "BIOS flashing light error codes for computers released between 2011 and January 2015" states you have a general system board failure, and therefore your vendor for the replacement motherboard should be contacted.

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When you get that motherboard replaced:

One or the other should lead you to on-screen instructions for recovery, but if the same recovery message shows up repeatedly, shut down the laptop, and go to another Windows machine to visit Software and Downloads at https://support.hp.com/us-en/drivers/laptops to download a BIOS recovery app file onto a blank USB flash drive to make a Recovery USB Flash Drive.

That page will ask for your PC's exact part number from the serial number sticker on the underside. Once you get there, make sure to change to the original Windows version your laptop first shipped with (since this machine ceased production before Windows 10 was released to manufacturing). Look on the laptop for the sticker which shows that version.

Launch the app after downloaded, and choose Recovery USB Flash Drive. When if finishes, close that app and then safely eject the flashdrive.

Then, insert the USB flash drive in the failing laptop, and use the combination keystroke/power-up process again.

Do Win-B and keep holding them down while you press-and-hold the power button for 3 seconds. Let go of the the Power button while still holding Win-B. If the Power light goes out, repeat with only 2 seconds press-and-hold of the power button.

If that does not bring up the HP BIOS Update, then repeat the above with Win-V instead.

Either should invoke the BIOS recovery, and with the USB flash drive just created, will reinstall your BIOS.

Comments

[Alex]

Blinking CAPS LOCK indicating an issue with motherboard or BIOS. Try to remove CMOS battery, disconnect battery and power supply then press and hold power button for at least 30 seconds. It could be an issue with power supply too, try to start computer on battery only with disconnected external devices such as HDD, CDROM, WiFi card.

[Appleoddity]

It’s not true that all the other boards are needed for the laptop to work. What is the relevance of saying that? Does the motherboard work when those items are disconnected? How do you know the motherboard was bad to begin with? How do you know the used motherboard you’re trying is any good? The only thing needed to power on the motherboard is power, ram, and a power switch. And the CPU of course which is probably permanent.

[Jacob Bruinsma]

Alex, I've done everything with and without CMOS battery. It seems to do less power cycling and indicating without the battery. On battery, same story. I've also had all devices disconnected.

[Jacob Bruinsma]

Appleoddity, I've had all boards disconnected, but then it just turns the fan on 100% and nothing else. Then connecting the boards one at a time show the same thing, in the end it needed the modem board plugged in to get back to this blinking error mode where I have at least some input on the system booting process. My old motherboard was bad because it heated up badly and dimmed my power supply LED when I plugged it in. New motherboard was tested according to seller, same exact model. No idea on any of the other components, don't have the parts to test that.

[Alex]

If you have a choice to barrow CPU to try out on your motherboard, it probably would help go further with issue investigation. (Use @SomeUserName when you replaying, otherwise people won't be notified)

[Jacob Bruinsma]

@Alex, wouldn't CPU throw a 1-blink error? But it's possible. I'm thinking now it may be graphics, since the monitor or VGA has not once turned on. I'm tempted to buy both parts and try that.

[K7AAY]

@Jacob, thank you for your diligence in steadily analyzing what's going on here. There's a convention here for the original poster to update the original post in lieu of putting useful added info into comments. Clicking on edit above ant to the left allows you to add in useful data in response to questions, e.g. "..done everything with and without CMOS battery.." and "..had all boards disconnected.."

[Jacob Bruinsma]

Wow, you were quick. I've reseated the memory at least 3 times, also tried single sticks (not sure if the machine can boot with 1 stick). I'm trying your key combinations and other tips now, I'll get back to you. Thanks!

[Jacob Bruinsma]

Win-B didn't do anything (2 or 3 sec power), Win-V caused a slow blink on the Caps-Lock LED and now my HDD LED is lit orange. No screen or VGA yet though. I'll try the recovery drive next.

[Jacob Bruinsma]

I still haven't had any VGA or monitor output, Win-V does give me that slow blinking Caps-Lock and steadily lights up my orange HDD led. When I plug in my USB stick with the installed HP_TOOLS partition from HP UEFI Support Environment, the USB stick blinks once.

[Jacob Bruinsma]

Caps-Lock + Num-Lock blink slowly, 5 times now. My orange HDD led stays lit.

[K7AAY]

five flashes as per HP's troubleshooting web page support.hp.com/us-en/document/c01732674 and its section titled "BIOS flashing light error codes for computers released between 2011 and January 2015" states you have a general system board failure, and therefore your vendor for the replacement motherboard should be contacted.