The USDJPY has settled in between some technical levels which is controlling the ups and downs.
On the top side, the 200 hour moving average at 149.157 is providing close resistance. Above that the high for the day at 149.315 corresponds with swing lows from last Friday's trade. Finally the 100 hour moving up to 149.421 (blue line in the chart below) would need to be broken to increase bullish bias.
Conversely, on the downside the 50% midpoint at 148.734 of the range since September 22 is another key level that if broken would increase the bearish bias. On a break below it, traders would look toward a swing area between 148.44 and 148.518. Move below that and the door opens for further downside momentum.
So buyers and sellers are battling it out. Technical levels are playing a role. Traders will be looking for the next break either higher or lower.