[SOLVED]HP 2760p Battery Light Flashing and Fails POST

Vortex6700

Member
Apr 12, 2015
107
4
36
Hello all! Please review my description of the problem and feel free to advise, discuss, or brainstorm.

HP 2760p convertible PC with the following specifications:

CPU: Intel i5 (Cannot see which i5)
Screen: Multitouch with Wacom Digitizer
RAM: 4gb DDR3
HDD: 320GB

This is all I know about the machine. Until yesterday, it booted up perfectly fine. Now the power button doesn't do anything and the battery light flashes white and amber. This happens regardless of AC or Battery.

A google search results in a few solutions, most referring to the manuals I have linked below. The battery light indicator is referred to in HP documents as signaling both "Low Battery" and "Battery Connection Failure."

**UPDATE** When attempting step 8 below, I noticed that there is a spark when I plug the ac power adapter into the HP 2760p. Repeatedly plugging the device in causes a hot plastic smell.


What I have on hand:

1x HP 2760p (The subject of this thread)
1x HP 2730p (Working fine)
2x HP OT06XL Batteries
Electronics tool kit and soldering station

The batteries show as fully charged both using the on battery status indicator lights and the HP 2730p.


Supporting Documentation:

http://support.hp.com/gb-en/document/c01732674
HP Troubleshooting Guide

http://www.manualslib.com/download/701389/Hp-Elitebook-2760p.html
HP 2760p Service and Maintenance Guide

What I have tried:

1. Battery Power Only: On battery connection, the battery light flashes white and amber. When the power button is pressed, nothing changes.

2. Battery and AC Power: Same as before. No other lights, beeps, fans, or hd spin.

3. AC Power Only: Nothing happens.

4. 1-3 with Battery from HP 2730p: Same Results

6. Hard Reset: After removing battery, peripherals, and ac power, I held the power switch for 30 seconds and waited 30 minutes. Steps 1-3 were completed with both batteries (with a hard reset in between) and no change was observed.

7. Disassembly of Laptop and removal of motherboard: With the motherboard alone connected to the battery, steps 1-3 were repeated with both batteries and no change was observed.

8. (Not Completed) Draining Battery: I have drained the battery to 50% using the HP 2730p and attempted steps 1-3. I noticed a spark and the tell-tale smell of hot plastic when playing with the plug. The smell seems to be coming from the plug area only. I might attempt to connect/disconnect repeatedly and see where the short is on the motherboard by the burn marks IF I give up on the repair.

I will attempt to drain the battery to it's lowest levels using a small incandescent bulb.


As stated earlier, please feel free to advise, discuss, or brainstorm. I will keep you up to date as I progress.

Thank you in advance for all of your help.

Edit: Update on step #8
 
Last edited:

Vortex6700

Member
Apr 12, 2015
107
4
36
[SOLVED] No thanks to you guys :triumph:

I managed to find that there were two shorts. One was at the AC Adapter, and the other was at the battery adapter.

I removed and re-soldered the sockets, and it works fine now.

Difficulty 3/5. No logic analyzer needed.


When removing and re-soldering, do not reference the second battery connection, as they are not the same. Take pictures before taking anything apart.
 

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