I made sure that the terminals and contact surfaces were thoroughly cleaned before I fitted the new battery. However when I removed the old battery I discovered that it was still giving 3V. Naturally I thought that the CMOS battery was dead so today I replaced it. I noticed that this machine loses its time and date each time the main battery is removed or goes completely flat. I have been working with laptops for the past 20 years so I am fairly conversant with their inner parts. I have an unusual problem with an Acer Asprire 4572 that I bought second hand a year ago. After browsing the web I have decided that this site is the most knowledgeable in these matters. I guess the CMOS chip must be faulty, which is why it won't reset ?. I thought that was strange as both PW's should be the same word etc.
This PC was working fine, I went into the setup a few days ago to check the user and admin passwords, but noticed the one was what it should be, but the other, which should have been the same word, just would not accept, giving wrong password error for the old password to be typed in etc.
When I switch on the PC, it tries to boot, then turns itself off for a few seconds, then turns itself on again and boots to the screen asking me for a password.
Only using M/B, power supply, 1 RAM card in first slot, 1 CPU, built-in graphics, PS2 keyboard, no mouse, no usb, no controller cards, no sound cards, no usb3, as plain as it can be. Pressed the main PC on/off button several times, etc. I left the M/B completely unplugged, no power, no battery, no hard drives, no cards, and the CLR_CMOS pins shorted for a day. In most cases you can identify a defective condenser, when fluid leaked out of the cover, or when the cylinder itself is arched. On older mainboards, it often happened, that the condensers get faulty. The cylinder is mostly green, blue or black, and has a pressed aluminum cover. Or use a second PC to check these components.Īn electrolytic condenser is a cylindrical electronic component that stores electricity.
The CMOS-Reset-Button works like a normal CMOS-Reset-Jumper.ĬMOS-Reset did not solved the problem! What can i do? with a paper clip) to reset the CMOS.ĬMOS-Reset-Button: On newer mainboards you'll find different buttons for e.g. Soldered points: Sometimes there is no connector strip and you'll only find 2 soldered points which must be bridged (e.g. To reset the CMOS move the jumper cap to position pins 2+3.Ģ-Pin CMOS-Jumper: Depending on the default position, you have to remove or place the jumper. There should be a label like JBAT1, RTCLR, CLRCMOS, CLRCMS, CMOS_CLEAR, Clear RTC, or similar.ģ-Pin CMOS-Jumper: The connector strip has 3 pins and the default jumper position is pins 1+2 (see picture). In most cases you can find the jumper (green jumper cap, see picture) nearby the CMOS-Battery.
Read the manual to find out how you can reset the CMOS! Because the procedure can be very different! For instance, most mainboards have to be completely dead, but there are others where you have to reset the CMOS when power is on. Inside the manual there should be a layout drawing which shows the jumper position.
Most mainboard manufacturers have a download section on their websites where you can find the manual of your specific mainboard type.