Becker Active 6 GPS Replacement Battery 3.7V 1200mAh

Becker Active 6 Series — 3.7V Li-Polymer Replacement Battery (SR3840100)

This 3.7V, 1200mAh Li-Polymer cell replaces the original SR3840100 battery in Becker portable GPS navigators. It fits the Active 6, Active 6 LMU Plus, BE B40, Transit 6 LMU, and several additional models in the same hardware family. Dimensions are 84.18 × 29.80 × 4.48mm — measure your existing cell before ordering if you are unsure of your variant.

• Active 6 family compatibility: Becker's Active 6 line and Transit 6 variants share the same battery bay dimensions, connector pinout, and charge-management circuit. The SR3840100 part number spans all of these because the PCB charge controller is identical across the range.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a Becker Active 6 unit. The onboard charge IC accepted the cell without fault flags, voltage regulation held steady under display-on GPS-active load, and the protection circuit tripped correctly at the low-voltage cutoff threshold.
• First fix after installation: After fitting this cell, power the navigator fully on outdoors before driving. A full power interruption triggers a cold start — the GPS receiver re-downloads almanac data and first satellite lock can take 5–10 minutes. Subsequent warm starts lock in under a minute.

GPS accuracy dropping at low charge on the Active 6

When cell voltage falls below roughly 3.5V under load, some Becker Active 6 units reduce GPS receiver sensitivity to protect remaining charge. The result is position drift or longer re-acquisition after tunnel exits. This is firmware-level power management, not a hardware fault. Keeping the battery above 3.6V during active navigation — via USB car charger — prevents the sensitivity reduction entirely.

Active 6 shutting off without a low-battery warning

The battery indicator on the Active 6 reads state-of-charge from a voltage curve calibrated to the original cell's age profile. A new cell has a flatter discharge curve than an aged one, so the indicator can read 20–30% and still trigger an immediate shutdown when load voltage sags under GPS + display demand. This is not a fault with the replacement cell. Discharge the new battery fully once, then charge to 100% to allow the firmware's voltage-to-percentage mapping to re-anchor to the new cell's curve.