[SOLVED] Cmos battery failure

Nov 15, 2019
7
1
15
I let my Dell 3750 sit for several years. Went to boot it up for a project and it gave Cmos battery failure (flashing lights code). Replaced the battery with a good one and still get the same error. Dell support says it is 7 years old like it means ancient or god forbid using a stick in a clay tablet. Dell says send it back and we will charge you to see if it can be repaired.
Level of confidence on that call was ZERO.
Is there anything that can be done to resurrect this machine or should I just sell it for scrap and parts.
 
Solution
Make sure the battery contacts do not have corrosion. If there is corrosion, just get rid of the board. Any corrosion at all will likely have leached into the layers underneath the surface and this is a one way street.

During any testing remove any components you don't need. For example, you don't need a hard drive attached to get to the BIOS, and if you have integrated graphics, then you probably don't need a discrete GPU graphics card. Only add components back in one at a time.

Before putting the new battery in, if there is any method of resetting the CMOS (usually shorting a jumper), then do that (a bad battery is the same thing, except you want to be sure the CMOS is truly reset after you've been testing...e.g, no battery and...
Make sure the battery contacts do not have corrosion. If there is corrosion, just get rid of the board. Any corrosion at all will likely have leached into the layers underneath the surface and this is a one way street.

During any testing remove any components you don't need. For example, you don't need a hard drive attached to get to the BIOS, and if you have integrated graphics, then you probably don't need a discrete GPU graphics card. Only add components back in one at a time.

Before putting the new battery in, if there is any method of resetting the CMOS (usually shorting a jumper), then do that (a bad battery is the same thing, except you want to be sure the CMOS is truly reset after you've been testing...e.g, no battery and jumper for 30 seconds, depending upon model). Once the new battery is in, if you can get to the BIOS, tell it to do a BIOS reset to default values. After that it might work. If you can't get to the BIOS I wouldn't have much hope.
 
Solution
Nov 15, 2019
7
1
15
the response may be of assistance to some for me the response assumes more knowledge of the situation than I have.
The cmos battery terminals are clean and there is power with the new battery. I looked for any information on resetting the cmos and I did not find any for my machine. I guess it IS boat anchor time.