Re: cisco 2911 no power

frankbarton1505 · ‎01-22-2019

Hello. I have 2 cisco 2911. one works fine, the other doesn't power up. no lights, fans, or anything.

I tried swapping the power supplies between routers. both psu's work fine. I did the fan assembly too. again, no problems there. I conclude the problem must be either the backplane or the motherboard. I strongly suspect the former. looking at the hardware replacement guids i can find no methodd of replacing or even accessing the back plane, yet they sell replacements on ebay so it nmust be possible to do it. Can anywone instruct me how? thank you.

Georg Pauwen · ‎01-22-2019

Hello,

since the PSU seems to work, the problem is likely with one of the components inside the chassis that connect the power supply to the motherboard. Depending on how much time you are willing to spend on it, you coud open the chassis and check for loose components or any visible damage to cables and/or connectors...

https://fccid.io/ANATEL/00548-10-01086/Manual-parte-3/59E875C8-EF90-46BB-A3D3-5D241A6C4328/PDF

frankbarton1505 · ‎01-22-2019

@Georg Pauwen wrote:
Hello,

since the PSU seems to work, the problem is likely with one of the components inside the chassis that connect the power supply to the motherboard. Depending on how much time you are willing to spend on it, you coud open the chassis and check for loose components or any visible damage to cables and/or connectors...

https://fccid.io/ANATEL/00548-10-01086/Manual-parte-3/59E875C8-EF90-46BB-A3D3-5D241A6C4328/PDF

yes that's the document i looked at. it doesn't mention the back plane. the motherboard board looks pristeine, no puffed capacitors or anything like that. I cannot find how toe get the backplane out. the chassis seemed to be rivetted rather than screwed, which makes things difficult as you can image. people must have been able to do it as they are selling spares on ebay.

Georg Pauwen · ‎01-22-2019

Hello,

have a look at the doument below:

https://www.cisco.com/c/en/us/td/docs/routers/access/hardware/notes/acsmodsp.html

The problem is: it can be literally ANYTHING in the chassis, and if you cannot spot it visually, you would have to use some sort of measuring tools to check which one is broken...

frankbarton1505 · ‎01-22-2019

@Georg Pauwen wrote:
Hello,

have a look at the doument below:

https://www.cisco.com/c/en/us/td/docs/routers/access/hardware/notes/acsmodsp.html

The problem is: it can be literally ANYTHING in the chassis, and if you cannot spot it visually, you would have to use some sort of measuring tools to check which one is broken...

yes i've looked at the document, and i agree, i do have multimeters and scopes to test gear but i'd hav e to know what pins on the backplane, contacts are meant to provide what. I cannot find such information on that document.