Battery losing charge. won't recharge on Probook 6470b, charge light blinks 9 times, then off

[chrondoodle]

The battery on my Probook 6470b gave out and would not charge. I got a new battery (Ninjabatt replacement for HP). The computer works fine with the new battery but won't charge up, either and the battery is losing charge. When the AC power is plugged in, the charging light blinks in white 9 times and then goes off. Computer will not run without battery when plugged into charger. I suspect the charger is no good, but don't want to invest in another charger only to find that's not the problem. I visited this forum several times already and none of the advice was helpful. I pulled the battery, discharged the power button for 30 seconds, tried to upgrade the BIOS but BIOS update is blocked, pulled and re-installed the RAM and pushed F2 at startup for system diagnostics, only to find that my system diagnostics will only check hard drive, boot up options, and language. It does not have a diagnostics menu like that shown on many of the responses to this forum. Why does the charging light blink 9 times and go off? Maybe this is a error code, but I can't find it anywhere.

[erico]

HI @chrondoodle 

Welcome to the HP Support Comm,unity forum!

I suggest that you download the latest version of the HP UEFI Diagnostics utility and install it. Run the system tests. Honestly, I have never heard of or seen a 9 blink diagnostics code. Run the long version of the system diagnostic.

Here is the HP Hardware Diagnostics web page. The HP UEFI Diagnostics utility is near the bottom of the web page. Click on the button to download it.

https://support.hp.com/us-en/help/hp-pc-hardware-diagnostics