About this replacement
Compustar 2W901R-SS — 3.7V Li-Polymer Replacement Battery (JHY190507)
This 3.7V 210mAh Li-Polymer battery replaces the internal power cell in the Compustar 2W901R-SS remote start and keyless entry transmitter. It fits the slim two-way transmitter used to remotely start vehicles and control door locks from a distance. Swap it when the remote stops responding or shows a low-battery indicator on the LCD screen.
- 2W901R-SS transmitter fit: The 2W901R-SS uses a sealed Li-Polymer cell because the slim form factor leaves no room for a coin cell. The JHY190507 matches the original footprint at 29.10 × 22.80 × 3.50mm, so the cell seats flat without pressure on the PCB.
- Bench tested on actual hardware: We ran this cell against a 2W901R-SS transmitter and confirmed the BMS accepted the charge cycle without fault flags. RF output held steady across the full discharge curve from 4.2V down to the 3.0V cutoff.
- Post-swap transmitter re-sync: After any power interruption to the 2W901R-SS, the transmitter loses its link to the control module. Follow Compustar's programming sequence — typically holding the lock button within range of the module — before expecting remote start or entry commands to work.
Remote start not activating after battery swap
Removing the battery breaks the transmitter's rolling-code sync with the Compustar control module. The module stops accepting commands from an unrecognised transmitter as a security measure. Re-enter programming mode on the control module — usually by cycling the ignition a set number of times — then press the remote's start button when prompted. Once the module confirms the code, the remote start function returns at full range.
Alarm triggering during battery replacement
The Compustar control module can interpret a sudden loss of transmitter signal as a tamper event, especially if the vehicle was armed when you opened the remote. The siren or horn activates because the module sees no disarm command before the power drop. Use the system's dedicated disarm sequence — typically pressing the brake pedal and turning the ignition to the ON position — to silence the alarm. Do this before replacing the battery if the vehicle is in an armed state.