HP Z VR Backpack G1 Maintenance And Service Manual page 58

Items
NOTE: Refer to battery replacement section
for removing/replacing the battery
The sections below are intended for authorized service providers/technicians.
NOTE: 2015 mWS does not have the power
cable between system board and power
connector on chassis
Tips and tricks
48 Chapter 7 Troubleshooting guide
Procedures
Verify battery condition/status
1. Check battery condition (overall result, cycle life, voltage, etc.) using HP PC
Hardware Diagnostics (UEFI) or HPSA tools.
2. Verify that battery is installed properly in battery bay without a gap and that latch
locks are tight (for models with removable batteries).
3. Check battery status light
lights, and POST error messages on page
discharged, preventing system from booting.
4. Determine whether the computer can turn on with battery only.
5. Remove service door and test with a verified working battery. If the computer
boots, inspect original battery before replacement.
6. Test battery with a verified working computer to verify that it is OK.
7. If there is still no boot, remove battery and boot on AC power only.
Verify AC adapter – voltage
1. Measure DC voltage output that should be around 19.5 VDC and acceptable voltage
range is from 18.5 – 20.5 VDC.
2. If the DC voltage is out of range, replace the AC adapter.
NOTE: This action requires a digital voltmeter.
Verify power button, power connector
1. Be sure that power button is not stuck.
2. Reseat power connector cable (if applicable).
3. Replace new power connector cable (if the cable exists and is defective)
4. To isolate faulty power connector cable and power button, technicians can short
power-on pads/pins to power up the computer. Contact HP Engineering for this
information.
Verify blinking lights (7. Status lights, blinking light codes, troubleshooting lights, and
POST error messages on page 39)
At this point, there should be sufficient power from the AC adapter to the system board.
Expect to hear the fan spinning and see blinking lights or error messages, (faulty
memory, HDD, etc.).
Verify system board
1. Test essential hardware configuration
on page 43, 12. Test with verified working configuration (hardware and/or
operating system) on page
removing nonessential parts.
2. If there is still no boot, replace system board.
Computer automatically boots without pressing power button when RTC 3V battery has
been removed. Therefore, after the service door and RTC 3V battery are removed, no
need to press power button from top side.
In essential hardware configuration, mWS G1 and G2 may require discrete GPU to boot.
However, mWS G3 can boot with integrated graphics.
(7. Status lights, blinking light codes, troubleshooting
39). Be sure that battery is not fully
(11. Test with minimum configuration
44, 13. Replace the system board on page 44) by