Becker Traffic Assist Pro 3.7V 1200mAh GPS Replacement Battery

Becker Traffic Assist Pro — 3.7V Li-ion Replacement Battery (38799440)

This 3.7V 1200mAh Li-ion cell replaces part number 38799440 in the Becker Traffic Assist Pro, Traffic Assist 7916, and Traffic Assist Pro Ferrari 7929 portable GPS navigators. These units lose the ability to hold a charge as the original cell degrades, leaving the device unusable away from a power outlet. This replacement restores full battery-backed operation for on-the-road navigation.

• Traffic Assist Pro and 7916 series compatibility: All three models in this fit list share the same 3.7V single-cell architecture, connector pinout, and BMS handshake protocol, which is why one cell number — 38799440 — covers the entire group including the Ferrari 7929 variant.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a GPS navigator test rig, confirmed the BMS accepted the cell without fault flags, and verified voltage delivery remained stable across screen-on and GPS-active load states.
• First fix after battery swap: After fitting this cell, power the unit on outdoors and allow it to acquire a satellite fix before driving. A full power interruption triggers a cold start — expect 5 to 10 minutes for the first fix versus under a minute for subsequent warm starts.

GPS accuracy reduced at low battery on the Traffic Assist Pro

When cell voltage drops below roughly 3.5V, some Becker GPS units reduce RF receiver sensitivity to protect remaining power. This shows up as position drift or a weaker satellite signal bar count — not a software glitch. The navigation firmware prioritises core functions over GPS precision at low voltage. Keeping the cell above 3.6V under load prevents the sensitivity reduction from triggering.

Traffic Assist Pro shuts off without warning before the battery indicator hits empty

The on-screen battery gauge in these units is calibrated to the original cell's discharge curve. A new or different cell can have a slightly different voltage-to-capacity curve, causing the shut-off threshold to trip before the visual indicator shows critical. This is not a faulty cell — it is a calibration mismatch. Run two or three full charge and navigation-use cycles to let the firmware re-anchor its shut-off estimate to the new cell's actual curve.