Need part number for fault code p0431 Mitsubishi montero 2001. Plz help

Question

I am trying to find a part based on a fault code p0431. The code come from a vehicle inspection and I desperately need to fix my moms car. It's a 2001 montero sports Mitsubishi. Also got two more faults and wonder if there are associated parts I can order as well: p0125 & p0155

Answer 1

P0431 warm up catalyst below efficiency

P0125 Insufficient coolant for closed loop operation  (engine coolant temperature)ECT excessive time for closed loop operation

P0155 - 02 sensor heater circuit malfunction Bank 2 Sensor 1

You only need to satisfy P0155. The front 02 sensor on bank 2, without a functioning 02 sensor you can expect the catalytic convertor to not work, because it is not working the front 02 is not working  it cause P0125 to code up. The problem for the part number there is so many Montero sport models ,