{"product_id":"fujitsu-pa3553-replacement-battery-3v-200mah-lithium","title":"Fujitsu PA3553 CMOS Backup Battery 3V 200mAh Lithium","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eFujitsu PA3553 \/ Amilo D7800 — 3V Lithium CMOS Backup Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3V, 200mAh lithium CMOS backup battery for Fujitsu Lifebook and Amilo systems, including models PA3553, MS2242, PA3515, and the Amilo D7800. It powers the RTC circuit and SRAM when the main battery is removed or the system is unplugged. Without it, the clock resets and BIOS settings are lost every time mains power is cut.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003ePA3553, MS2242, PA3515, Amilo D7800 compatibility:\u003c\/strong\u003e\n    These models share the same motherboard RTC circuit footprint and connector spec — the CMOS cell connects via a two-wire lead to a dedicated retention rail that operates independently of the main battery.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We confirmed the cell holds above the 2.8V retention threshold under continuous SRAM load and that the connector seats correctly without modification to the socket spring.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eAfter-install BIOS step:\u003c\/strong\u003e\n    After fitting the new cell, enter BIOS immediately, set the correct date and time, then save and exit. The RTC circuit resets to a default value after any power interruption — it will not self-correct and must be set manually after the swap.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBIOS clock resetting to 2000 after every power cycle\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe RTC on these Fujitsu boards draws from the CMOS cell continuously, even when the laptop is fully powered off. Once cell voltage drops below 2.8V, the retention rail can no longer hold the RTC register state. The clock falls back to the factory epoch — typically 1 January 2000 — on every cold boot. Replacing the cell and setting the correct time in BIOS resolves this immediately; no firmware flash or BIOS reset is needed.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCMOS checksum error appearing on boot after cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eA checksum error on first boot after replacing the CMOS cell means the BIOS compared stored settings against what the SRAM now holds and found a mismatch — the old depleted cell left corrupted or zeroed values in SRAM. This is expected, not a sign the new cell is faulty. Enter BIOS, load optimised defaults, set the correct date and time, then save and exit. The error will not reappear once valid settings are written back to SRAM.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43339836653658,"sku":"BWCS-DE6500BU-1","price":31.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43339836686426,"sku":"BWCS-DE6500BU-2","price":34.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43339836719194,"sku":"BWCS-DE6500BU-3","price":37.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-DE6500BU-1.webp?v=1778366787","url":"https:\/\/batteryweb.com\/products\/fujitsu-pa3553-replacement-battery-3v-200mah-lithium","provider":"BatteryWeb","version":"1.0","type":"link"}