About this replacement
Becker Traffic Assist Z200 Series — 3.7V Li-ion Replacement Battery (S30)
This 3.7V 720mAh Li-ion cell replaces the OEM battery in the Becker Traffic Assist Z200, Z201, Z203, and Z204 portable GPS navigators. It matches the original's voltage, connector, and physical footprint at 50.09 × 36.67 × 6.75mm. Capacity is 720mAh (2.66Wh), sourced to match the factory specification.
- Z200–Z204 platform fit: These five models share the same internal battery bay dimensions, connector pinout, and BMS communication protocol, which is why one cell covers the whole range. The 3.7V nominal rail is consistent across all variants.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Z200 platform. The BMS accepted the cell without error, balanced correctly at 4.2V peak, and held the low-voltage cutoff at the expected threshold without tripping prematurely.
- First fix after fitting: After fitting this cell, power the unit on outdoors before driving. The GPS performs a cold start after any full power interruption — first satellite acquisition takes 5–10 minutes. Subsequent warm starts drop to under a minute once the almanac is cached.
GPS accuracy reduced at low battery on the Z200
When the Z200's cell drops below roughly 3.5V under load, the unit reduces RF receiver sensitivity to conserve power. This shows up as slower position updates and occasional route recalculations on roads the unit previously tracked cleanly. It's a firmware-level power management decision, not a hardware fault. Fitting a fresh cell and letting the unit calibrate its battery indicator over one full charge cycle restores normal receiver performance.
Z200 shuts off without warning before the battery indicator hits zero
The on-screen fuel gauge on these units is calibrated against the original cell's discharge curve. A replacement cell with a slightly different discharge profile can cause the indicator to read 20–30% remaining right up until the BMS trips the low-voltage cutoff. This isn't a battery fault — it's the gauge reading a curve it wasn't calibrated for. Run one full charge-to-cutoff cycle and the firmware will recalibrate the indicator to the new cell's profile. After that cycle, the gauge should track accurately down to 3.5V before shutdown.