{"product_id":"rand-mcnally-tnd-750-replacement-battery-37v-5000mah-li-polymer","title":"Rand McNally TND-750 GPS Replacement Battery 3.7V 5000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eRand McNally TND-750 — 3.7V Li-Polymer Replacement Battery (AHB865958)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V, 5000mAh Li-Polymer cell replaces the AHB865958 battery in the Rand McNally TND-750 GPS navigator. The TND-750 is a truck and automotive navigation device that runs on internal battery power when disconnected from a vehicle power source. Fit this cell when the original no longer holds a charge or the device shuts down unexpectedly during use.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eTND-750 fit:\u003c\/strong\u003e\n    The AHB865958 is the sole internal cell for this navigator. Voltage, connector pinout, and physical dimensions — 61.00 × 58.20 × 8.20mm — match the original exactly, so the device's charging circuit and low-battery indicator read the new cell correctly from first boot.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge and discharge passes on the TND-750 platform. The BMS accepted the cell without error flags, and the charge circuit reached full cutoff voltage at 4.2V as expected.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eCold-start satellite acquisition after swap:\u003c\/strong\u003e\n    After fitting this cell, power the TND-750 on outdoors and let it acquire a satellite fix before driving. The GPS performs a cold start after any full power interruption — first fix typically takes 5–10 minutes, compared to under a minute on a warm start.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eGPS accuracy dropping at low battery on the TND-750\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eSome GPS units reduce receiver sensitivity as battery voltage drops, prioritising power conservation over signal strength. On the TND-750 this can show up as position drift or slower route recalculation near the end of a charge cycle. The fix is straightforward: keep the device charged above 20% during active navigation. If accuracy issues appear mid-route, connect the device to vehicle power — the GPS receiver will restore full sensitivity within a few seconds of stable voltage.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eTND-750 shutting off without warning before the battery indicator hits empty\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eAfter a full battery swap, the TND-750's fuel gauge is uncalibrated — it has no charge history for the new cell. The device may cut power abruptly at what looks like 15–20% remaining because the low-battery threshold was mapped to the old, degraded cell's discharge curve. Run two full charge-to-discharge cycles to let the firmware recalibrate the indicator against the new cell's actual capacity. After that, the low-battery warning will trigger at the correct voltage, which is approximately 3.5V under load for this chemistry.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43377556586586,"sku":"BWCS-RMT750SL-1","price":39.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43377556619354,"sku":"BWCS-RMT750SL-2","price":46.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43377556652122,"sku":"BWCS-RMT750SL-3","price":51.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-RMT750SL-1.webp?v=1778771668","url":"https:\/\/batteryweb.com\/products\/rand-mcnally-tnd-750-replacement-battery-37v-5000mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}