HL2 No Ethernet Activity and Lnk LED - No EtherNet connection

[Terry Long]

Hello All, 

I ah hoping someone has an idea on how to troubleshoot one of my HL2 Build 8 boards.

I have two boards, one is fine but the other doesn't get any Ethernet Act LED or LNK lights, and the device doesn't appear (of course) anymore on my network.  I use the good board as a reference point to compare to.

I had a 13.8v switching supply for this board which got hit with 110v spike (I believe).  Had very unstable power during a storm which took out the switching supply. I changed out bad supply to a good supply, and now neither Ethernet LEDs will light when powered and connected to my Lan switch.  Using the same supply and LAN connection on the other board works fine and its IP address is recognized on the network..

I measured all the power test points for U4 (KSZ9031RN) and all points measured power per the data sheet and schematic.  I was not sure how I might test CN3 MagJack?  I have not completed further testing and thought I'd ask for some help.

I grounded out the Key/PTT and repowered the device to reset the device back to Factory gateware.  No change after doing this troubleshooting step.  

I would appreciate any thoughts about what to verify or test to see what needs to be replaced or reprogrammed?

Kind regards,

Terry N8AB

[Steve Haynal]

My guess is that U4 and/or the network magnetics were destroyed in the strike. There is no really good way to test. I try first replacing CN3 as that is the easiest.

Does the network clock still come up? Without any network cable connected, one LED should be flashing if the clock is up.

73,

Steve

kf7o

[Terry Long]

Happy Sunday Steve.  

Thank you for your kind assistance.   The clock led (1) on the HL is flashing.  I’ll order the replacement for CN3 and give that a try.  

Terry, N8AB. 

[Terry Long]

Hello Steve and Group,

I replaced the MagJack to new one (learned alot about how to remove solder from all the holes..)  - still have no Ethernet Act LED or LNK lights.  Led 1 (clk) is flashing,  LED5 is solid on.  Any ideas about what else I should test or explore?   

Terry N8AB

[Steve Haynal]

Hi Terry,

Sorry to  hear that. I was hoping it would be the MagJack as that is the easiest to replace. Several years ago I did have to replace the KSZ9031 (or KSZ9021 in newer units) because of a lightening strike. That would be my next recommendation if you want to continue.

73,

Steve

kf7o