The data-erasing mechanism is a promising cost-efficient option for future broadband access networks. This paper analyzes the data erasure efficiency of the Fabry Perot Laser Diode(FPLD) at a speed of 5 Gb/s based on bidirectional wavelength division multiplexed passive optical networks (WDM PONs) using the carrier remodulation technique. The effects of many parameters such as the biasing current, extinction ratio, confinement factor, and injection power demonstrate the data erasure efficiency of the FPLD in the upstream bidirectional remodulation PON system are discussed. The novelty of this study is the very high front facet reflectance results are demonstrated. A range of injection power from -25 dBm to 0 dBm and an FPLD bias current of 20-100 mA were applied to the system. The injection power below 0 dBm and bias current above 30 mA provide successful transmission of upstream data. The FPLD can suppress the residual downstream extinction ratio <0.5 dB.